ANNUAL RECORD or SCIENCE AND INDUSTRY FOR 1878 EDITED BY SPENCER F. BAIRD WITH THE ASSISTANCE OF EMINENT MEN OF SCIENCE / NEW YORK HARPER & BROTHERS, PUBLISHERS FRANKLIN SQUARE 1879 'j ANNUAL RECORD OF SCIENCE AND INDUSTRY FOR 1871. U I it i< i 1872 U I a 41 t 1873 U 4 u U 4 1874 U ( (( U I 1875 i: i u 11 1 187G t. i n U l 1877 i. i u U I 1878 Edited by Spencer F. Baird, Secretary of the Smithsoni with the Assistance of Eminent Men of Science. Cloth, $2 00 per volume. The complete Set, 8 vols an Institution 8 vols., 12mo ,., for $15 00. Published by HARPER & BROTHERS, New York. in?" Any of the above works sent by United States, on 7>ia?7, postage prepaid, to receipt of the price. any par t of the Copyright, 1ST9, by Harpkb & Brotiucrs. PREFACE. The present volume is the eighth of a series commenced in 1871, and which, although entirely unconnected with a work having somewhat the same object the "Annual of Scientific Discovery" took up the record of scientific and industrial progress where the latter left it off, after having been published since 1850. A modification of the original plan of the " Annual Record" was commenced in the volume for 1877. Pre- vious to that it consisted of two parts first, a general summary of progress in the various branches of science ; and, secondly, a series of abstracts of special papers, credit- ed to the work in which they were published. These ab- stracts, although prepared by several specialists, were with- out indication of their authorship. The experience of several years showed that in attempting to give abstracts of anything like the most important announcements of the year, more space was required than could be spared for the purpose ; and it was therefore determined to en- large the scope of the first division, and make it include a greater amount of detail, each summary to be prepared by some eminent specialist, and to be headed by his name. This plan was found to give entire satisfaction to the patrons of the "Annual Record," and it has therefore been followed on the present occasion. In the table of contents will be found an analysis of the several articles, while a very minute alphabetical index will permit easy reference to any particular facts recorded. Spencer F. Baird. Smithsonian Institution, March 1, 1879. TABLE OF CONTENTS. PREFACE Page iii ASTRONOMY. By Edward S. Holden, U. S. Naval Observatory. Wash- ington 1 Introduction 1 Nebulae and Clusters; Nebular Hypothesis; Construction of the Heavens 2 New Stars; Variable Stars; Red Stars; Proper Motions, etc. . 7 Double, Binary, and Multiple Stars 8 Star Catalogues and Maps 10 The Sun 12 Solar Eclipses 15 Transit of Mercury, May 6, 1878 24 Transit of Venus and Solar Parallax 26 The Discovery of Vulcan 27 The Planets and Satellites 30 The Moon 34 Comets ; Meteor Streams 36 Zodiacal Light ; Meteorites 37 New Observatories, New Instruments, etc 37 Astronomical Bibliography, etc 39 Miscellaneous Notes 42 Reports of American Observatories 46 Allegheny City, Pa. : Allegheny Observatory 47 Brooklyn, N. Y. : Private Observatory of H. M. Parkhurst 49 Buffalo, N. Y. : Private Observatory of Henry Mills 49 Cambridge, Mass. : Harvard College Observatory 49 " " Physical Observatory of L. Trouvelot 51 Chicago, 111. : Dearborn Observatory 53 Clinton, N. Y. : Litchfield Observatory of Hamilton College 55 Columbia, Mo. : Observatory of the University of the State of Mis- souri k Columbus, O. : Ohio State University 58 Easton, Pa. : Lafayette College Observatory 59 Elizabeth, N. J. : Private Observatory of Charles W. Pleyer, Esq. ... 59 Fordham, N. Y. : Private Observatory of W. Meikleham, Esq 60 Fort Dodge, la. : Private Observatory of F. Hess, Esq 60 Germantown, Pa. : Private Observatory of Henry Carvill Lewis, Esq. Gettysburg, Pa. : Observatory of Pennsylvania College ,; 1 Glasgow, Mo. : Morrison Observatory *>4 v i TABLE OF CONTENTS. ASTRONOMY Continued. Hartford, < 'mm. : Private ( observatory of 1>. W. Edgecomb, Esq. Page 65 Hastings, N. Y. : Private Observatory of Henry Draper, Esq 05 Haverford, Pa. : I Observatory of Haverford < Jollege 65 Jackson, Mich. : Private Observatory of < >. Mulvey, Esq 65 Lowell. Mass. : Private Observatory of < >. ( '. Wendell, Esq 66 Mt. Lookout. ( ). : < lincinnati Observatory 06 Nashville, Temi. : Private Observatory of Edward C. Barnard, Esq.. 67 New Brunswick, X. J. : Sehanek Observatory of Rutgers College 67 New Haven. Conn. : Observatory of Yale College 68 New York, N. Y. : Private ( Observatory of William T. Gregg, Esq. . . 69 < Oxford, Miss. : Observatory of the University of Mississippi 69 Peconic, Suffolk Co., N. Y. : Private Observatory of George W. Fitz, Esq * 69 Phelps, N. Y. : Private Observatory of William Robert Brooks, Esq. . 70 Poughkeepsie, N. Y. : Observatory of Yassar College 70 Providence, R L: Private Observatory of F. E. Seagrave, Esq 70 Rochester, N. Y. : Private Observatory of Professor Lewis Swift 71 San Francisco, Cal. : Office of u The James Lick Trust" 72 South Bethlehem, Pa. : Sayre Observatory of Lehigh University... 73 St. Louis, Mo. : Observatory of Washington University 73 Tarrytown, N. Y. : Private Observatory of C. H. Rockwell, Esq 74 Troy, N. Y. : Proudfit Observatory 74 Washington, D. C. : U. S. Naval Observatory 75 Willet's Point, N. Y. : Field Observatory of Engineer Battalion 76 Yellow Springs, O. : Observatory of Antioch College 76 The Observatories of Italy 76 The Observatory of Palermo 77 The Observatory of Naples 77 Observatory of the Roman College 78 Observatory of the Capitol 78 ( >bservatory of Florence 79 ( Observatory of Bologna 79 ( Observatory of Modena 79 Observatory of Padua 80 ( >bservatory of Milan 80 < 01 iservatory of Turin 80 I'm I Observ \ Tories ok Portugal 81 The Lisbon Royal Astronomical Observatory 81 The Coimbra Observatory . , 81 The Observatories of Great Britain and Dependencies 82 Greenwich Observatory 82 Radcliffe ( Observatory, Oxford 82 University ( observatory, Cambridge 82 1 Minsink Observatory 82 Kiw < Observatory 83 Temple Observatory. Rugby S3 ' I ' TABLE OF CONTENTS. v ii ASTRONOMY Contin ued. Dr. Huggins's Observatory Page 83 Cape of Good Hope Observatory 83 Melbourne Observatory 83 Other Observatories ob 1 Europe 83 Observatory of the Academy of Sciences, Berlin 83 University Observatory, Bonn 84 Royal Observatory, Brussels 84 Dlisseldorf Observatory : 85 Gotha Observatory 85 Private Observatory of Herr von Konkoly, O'Gyalla, near Kornorn. 85 Hamburg Observatory 86 University Observatory, Leipsic 86 Private Observatory of Dr. Hugo Gericke, Leipsic 86 University Observatory, Lund 86 University Observatory, Milan 86 University Observatory, Mannheim 87 University Observatory, Moscow 87 Astrophysikalisches Institut, Potsdam 88 University Observatory, Stockholm 88 University Observatory, Strasburg 88 University Observatory, Warsaw 89 Imperial Observatory, Vienna 89 University Observatory, Zurich 89 Addendum 89 PHYSICS OF THE GLOBE. By Cleveland Abbe, with the assistance of Professor C. G. Rock wood, of Princeton, N. J 91 The Earth : Internal Condition 91 Underground Temperature 92 Vulcanology 96 Seismology 97 Notable Earthquakes and Eruptions 102 Terrestrial Magnetism 105 The Ocean: Depth 112 Density 114 Currents 115 Equality of the Surface Levels of the Atlantic and Pacific Oceans. . 117 Tidal Currents in the Gulf of Maine 117 Tides and Waves 118 The Atmosphere: Institutions, Observers, General Treatises, etc 119 General Treatises 134 Apparatus and Methods 148 1* V1 ii TABLE OF CONTENTS. PHYSICS I !' THE 7 New Form of Micrometer 359 New Test-object 359 Self-centring Turn-table 3G0 Theoretical Limit of Aperture 3G1 Micro-organisms, Bacteria Germs, Sporls, etc 3G1 Anaerobiosis of Micro-organisms 3(11 Organisms Suspended in the Atmosphere 3G2 Schulze's Mode of Intercepting the Germinal Matter of the Air. . . 3G3 Action of very Low Temperatures on Bacteria 364 Staining and Preparation of Bacteria 3G4 Examining, Preserving, and Photographing Bacteria 3G5 Measurement of the Diameter of the Flagella of Bacterium Pernio. 366 Life History of a Minute Septic Organism 367 Bacteria in Splenic Disease 367 Infusoria, Diatoms, Radiolaria, etc 367 Trembley's Experiments in Turning a Hydra Inside Out 367 The Foraminifera and Polyeystina of the North Polar Expedition, 1875-76 368 Radiolaria 368 Multiplication of Khizopods 368 Supposed Radiolarians and Diatomacea; of the Coal-measures 369 Revivification of Diatoms 369 Parasites on a Diatom 370 Diatoms in Colored Liquids 371 Isthmia nervosa : a Study of its Modes of Growth and Reproduction . 371 I [SSUE-STALNING, 1>looi>, etc 372 Structure of the Colored Blood-corpuscles 372 Rapid Staining by means of Carmine 374 < mid-staining, and the Termination of the Nerves in the Unstriated Muscles 374 Mix ill am.oi - 375 Nt >w Arams 375 Insect Dissection 375 TABLE OF CONTENTS. xi MICROSCOPY Continued. Pedesis Page 375 New Journals 377 National Microscopical Congress 377 The Limit of Accuracy of Measurement with the Microscope 378 Microscopic Tracings of Lissajous Curves 378 ANTHROPOLOGY. By Professor Otis T. Mason, Columbian University, Washington, D.C 379 Archaeology 381 America 381 Europe 385 Africa 388 Asia 388 Oceanica 389 Ethnology 390 Anatomy, Physiology, and Psychology of Races 390 Ethnography 393 America 393 Europe 395 Africa 396 Asia 397 Oceanica 398 Demography 398 Philology 399 Culture 401 Aliment 401 Edifices 402 Vessels 402 Implements 402 vEsthetic Culture 403 The Family 403 Social Life 403 Religion 404 Instrumentalities 404 Apparatus 404 Meetings and Transactions 405 ZOOLOGY. By Dr. A. S. Packard, Jr., Professor of Zoology and Geology, Brown University, Providence, R. 1 409 General Zoology 409 Treatises 410 Explorations 410 Geographical Distribution of Animals 415 The Hypothesis of Evolution 416 Dimorphism 419 xii TABLE OF CONTENTS. /( ><>u H}Y Continued. Protection, Resemblance, and Coloration Page 410 ( reneral Embryology 422 In\ i B i i BB \ n.s 423 Protozoa 423 Echinoderms 428 Worms 428 Mollusks 432 ( Srnstacearis 436 Insects 442 VERTEBRATE ZOOLOGY. By Professor Throdork Gill, of Washing- ton, D. C 455 Introductory 455 Origin of Vertebrate Limbs 456 Fishes, etc 458 North American Fresh-water Fishes 458 Vascular Dentine and Movable Teeth in Fishes 460 Various Physiological Adaptations of Fishes for Aerial Respiration. 462 Egg-laying Sharks and Rays 464 Oeep-sea Fishes 464 Annual Fishes 406 Fresh-water Suckers 407 The North American Trout and Salmon 467 Deep-sea Angler Fishes 470 Amphibians and Reptiles. . 472 Differences in Development of New-born Salamanders 472 Natural Selection Exhibited in the Development of Amblystoma Larvae 474 Oral Gestation in Amphibians 476 Reptiles Nearest to Mammals 476 Birds 477 The Pubic Bones of Birds 470 The Moulting of Parts of ^he Corneous Covering of Bills in Birds. . 470 The Genus Mcsites 481 A False I 'nder-tail in Storks 482 Mammals 483 The Primary Zoogeographical Regions of the Earth as Determined by the Mammals 4S1 The Species of Hats 487 Suborder Rlicrochiroptera \ Family Vespertitianidae.. 400 Group 1. Plccoti ) Whales of the Ziphiid Family 401 Size of the Tiger _ 4;)^ The Alleged Hermaphrodism of the 1 1 vena 403 The Placenta] Characteristics of the Sirenians 404 A Supposed NVw Gorilla 405 TABLE OF CONTENTS. x jii VERTEBRATE ZOOLOGY Continued. Chronological Palaeontology of the Vertebrates Page 496 The Dipnoans a Predominant Type of the Palaeozoic Age 496 Ceratodus in the American Jurassic 497 An American Ichthyosauroid Form 498 An American Jurassic Mammal 499 The Miocene Mammalian Fauna of Oregon 499 BOTANY. By Professor W. G. Farlow, Boylston Hall, Harvard College, Cambridge, Mass 501 Progress in America 501 Phanerogams 50 1 Higher Cryptogams 504 Thallogens 505 Lichens 505 Algae 506 Vegetable Anatomy and Physiology 507 Miscellaneous 509 General 510 Phanerogams 510 Anatomy and Morphology 511 Higher Cryptogams 512 Thallogens 514 Diseases of Plants 519 Bacteria 520 Vegetable Physiology 522 Herbaria, Gardens, etc 524 AGRICULTURE AND RURAL ECONOMY. By Professor W. O. Ax- water, Wesleyan University, Middletown, Conn 525 I. General Characteristics of Recent Progress 525 Union of Science with Practice in Agriculture 525 Status and Progress of Agricultural Science in 1878 526 Agricultural Science in Europe 526 Agricultural Science in the United States 527 II. The Atmosphere as Related to Vegetable Production 527 Agricultural Meteorology 527 Atmospheric Electricity 528 Influence of Atmospheric Electricity upon the Nutrition of Plants 528 Influence of Electricity upon Water -evaporation and upon Plant-growth 529 III. The Soil as Related to Vegetable Production 530 Physical Properties of the Soil. Agricultural Physics 530 Relations of the Soil to Heat , 531 xiv tabu; of contents. AGRICULT1 RE AND RURAL ECONOMY Continued. The Thermal Capacity of the Constituents of Soils Page 531 The Propagation of the Heal in the Soil 532 Effect of ( lompactness and Looseness of the Soil upon its Tem- perature 532 The Absorption and Emission of Heat by Soils 533 The [nfluence of the Color of Soil upon its Temperature 534 The Influence of Plant-covering and Shade upon the Tempera- ture of the Soil 534 [nfluence of Exposure on Soil Temperature 535 Relations of the Soil to Water 535 Permeability of the Soil to Water 536 Water-holding Capacity of the Soil 53G Evaporation of Water from the Soil 536 Effect of Loosening the Surface of the Soil upon Evaporation.. 537 Influence of Hoeing and Rolling the Soil 537 Experiments on Evaporation of Water from the Soil 538 1 'hysical Properties of Clay Soils 538 The Properties of Clay 538 Inlluence of Clay in the Soil 539 Reasons for Effects of Lime and Mineral Salts on Clay Soils. . . 510 Chemical Properties of the Soil. Soil Absorption 540 Absorption by Exchange of Bases 541 Absorption without Exchange of Bases 542 Restoration of Absorptive Power 542 Absorptive Powers of Different Layers of the Same Soil 542 Use of Lime and Marl in Soils 543 Value of Lime in Poor Sandy Soils 544 Further concerning Chemistry of Soils 544 Carbonic Acid in Soils 544 Fertility of Volcanic Soils 545 Analysis of Soils 545 Nitrification 546 Nitrification by Organized Ferments 547 Experiments on Nitrification by Warrington 547 Professor Storer on the Ferment Theory of Nitrification 548 Further Experiments by Schloessing and Miintz 548 What Kinds of Organisms Cause Nitrification? 548 Agency of Metallic Oxides in the Formation of Nitrates 549 IV. Tin-: Plant 549 ( Ihemifltry and Vegetable Physiology 549 ( ihlorophy] and the Formation of Starch 550 Whal Becomes of the Carbohydrates that are Formed in the I Draining op the Zuyder-Zee 578 ST. GoTHARD TUNNEL '. 580 A Deep Ska IIauuor for the Port of Boulogne 580 Tim: ( 'iiannel-tunnel Project , 580 Brddoing the Firth of Forth 581 A Railway Bridge across the Tay, at Dundee 58L 'I'm; Railway Bridge over the Duoro River 581 An Underground Railway for Paris 582 Steam-heating for Cities and Towns .">*:_> I' rn.izA iion or Solar Heat 583 Steam Road-wagons 583 TECHNOLOGY. By William H. Wahl, Ph.D., Philadelphia, Pa 585 Comparative Merits of Dynamo-electric Machines 585 Telegraphy 58G The Electric Light 588 The Fuel of the Future 591 ( j as-engines 594 The Incrustations on Brick Walls 59-4 i ridescent glass 595 Artii - k ial Production of Corundum Gems 590 The Ammonia Process of Soda Manufacture 597 Lamp-black from Natural Gas 598 \ i \v Caledonia Nickel 598 Plating Metals by Galvanic Means 599 Tin Protection of Iron Surfaces GO I Bala ta 601 New Explosives 602 INDU ST RIAL STATISTICS. By William FI. Wahl, Ph.D., Philadel- phia, Pa 003 General Revtew <>i the Iron Trade of the United States i < R 1877 003 Production of Pig-iron in 1877 603 A Comparative Tabulation of Pig-iron by States 605 Prodi n<>\ eriodicalhj va- ried. From 1785-1827 it was p B; 1856-65 it was v F 4 ANNUAL RECORD OF SCIENCE AND INDUSTRY. or v v F; from l s OS-7 7 it was again p B. It deserves at- tention. In Vol. III. of the Moscow Observations, Professor Bredi- chin has given his observations to determine the parallax of the nebula II iv. 37. The series extended over sixty-five nights, and comprised eight measures of Ac on each, night. The observations are grouped into twelve groups. The par- allax resulting is 0.065" 0.040". This includes the tem- perature correction of the screw. If the mean value of the screw be used without such correction, the parallax results as 0.009"0.041". Thus this nebula appears to be at the same distance as the (single) comparison star. Dr. Dreyer has published his supplement to the "General Catalogue of Nebulae and Clusters of Stars"' (Herschel). It contains, first, notes and corrections to the catalogue ; and, second, a continuation of this. The numbering is continued from 5079 (Herschel's highest number) to 6251. Of course this sum includes errors, duplicates, possible comets, etc., and on this account it has been doubted whether the time for the systematic catalogue of Herschel had come in 1864. The immense convenience of it as a printed working-list quite overbears any possible want of logical arrangement ;. and Dr. Dreyer's work is a much-needed supplement, and is edited with great care. Dr. Doberek has given in Nature (February 14, 1878) an abstract of D' Arrest's Undersogelse on spectra of nebulous stars, which will be valuable "to English readers, the original paper being almost unknown. About 6000 nebula' were known in 1872; of these 150 have been examined with the spectroscope only one-fortieth part. Of these about three fourths give the continuous spectrum, while only one fourth are true gaseous nebulae. Gaseous nebulae are, with few ex- ceptions, characterized by greenish-blue light, sharply defined circular or elliptic disks, and often have bright condensations within, almost stellar in appearance. A few are, however, large, irregular, and complicated, like nebula Ononis, for ex- ample. The ray-like elongated nebula) are, so far, always characterized by a continuous spectrum. The characteristic lines of a gaseous nebula have the wave-lengths, according to D'Arrest, (A) 5004.0, (B) 4956.6, and (C) 4860.6, with a fourth line occasionally present. From a great number of ASTRONOMY. 5 observations, Bredichin gives these: (A) 5003.9 1.2, (B) 4957.9 11.4, (C) 4859.23.1. Professor Holden has made a determination of the relative brightness of the different parts of the nebula of Orio?i, and for this purpose has used a photometer devised by Dr. Has- tings, of the Johns-Hopkins University. These photometric determinations show that this instrument is capable of giv- ing excellent results. Dr. Yogel, of the Potsdam Observatory, has published the results of measures on the cluster x JPersei, made in 1867-70 by means of the 8-inch refractor at Leipsic, with the object of fixing the relative positions (and magnitudes) of the stars of this cluster, so that any future change may not pass unde- tected. 176 stars, in all, have been fixed in position by the filar micrometer. The field was bright, and a magnifying power of 145 diameters was employed throughout. The va- rious sections of this work of 36 quarto pages treat of the following subjects : 1. T lie position of the instrument; the determination of the parallel. 2 contains an investigation of the position-circle , and of the value of the revolution of the micrometer. The zero of the micrometer is dependent upon the position of the instru- ment, and also upon the kind of illumination of the thread. The value of the revolution is found from transits on twenty nights, from November, 1867, to May, 1870. During all this time the reticle was left at the same distance from the objec- tive, and the thermometric coefficient resulted +0.001581" t in Reaumur's scale. The magnitude and the sign of this Dr. Yogel explains by the fact that the focal point was not determined each night (as he says is usual), and lie correctly points out the necessity of leaving the focus unchanged for such observations, and for determining the value of the screw during the series itself. 8 3 deals with the methods of observation and reduction, The brighter stars less than 10 magnitude were determined from measures of p and s with four selected stars of the group. These four were connected by measures of p and s and also Aa and Ac; and they were further connected witli two stars of the cluster h Persei, which had been observed with the Bonn meridian-circle. For each pair of the brighter ANNUAL RECORD OF SCIENCE AND INDUSTRY. stars at least four nights' observations were made. The re- ductions are complete, and the observations are reduced to 1870.0. The fainter stars (10-12 mag-.) were observed by Aa and A(~ with other stars at least on two nights for each star. B t deals with the accuracy of the observations, and first, for the brighter stare, the probable error of a single observa- tion in 8 is found to be 0.228", in p (reduced) 0.306". The probable errors for the mean of each night are more im- portant, and result as follows (no dependence of the probable errors on the distance or the position-angles being evident) : probable error of one night in s, 0.190", in p (reduced) 0.165". For the final position (at least four nights) these become, in s, 0.092"; in p, 0.080". For the Ao and Ao of the brighter stars these are 0.097" in R. A., .089" in KT. P. D. The positions for the fainter stars are determined within less than 1" in each co-ordinate, which Dr. Yogel considers suffi- cient for his purpose. 5 treats of the determinations of the brightness of the stars of this cluster. The 1*76 stars of the cluster range be- tween the 6.5 and 13 magnitudes. Each one of the fainter stars (higher than 10 mag.) was determined by eye estimates of magnitude at least five times ; the probable error of the mean is 0.14 magnitude. The brighter stars were determined on several evenings by the eye, and on two nights each was compared by a Zollner photometer with one of the standard stars. A table (p. 12) gives the magnitudes of the brighter stars, 1st, by eye (Yo- gel); 2d, by eye (Argelander) ; 3d, photometric magnitude^ assuming the lio-ht ratio -.-ttt, or 0.397. The agreement is remarkable, but the table shows (what was already known) that Argelander's magnitudes higher than 9.0 m make the stars too bright. 6 gives the observations of the stars (in tabular form), and the results. A difference between the spring and au- tumn observations, in both A and A3, of one of the stars in- dicates possibly a parallax of about 0.3". g : gives the observations of the fundamental stars, and catalogue of the 30 brightest shim. The observations are of relative A and \l of the four fundamental stars, and of two of Argelander's stars in h Persei, and also meridian observa- ASTRONOMY. 7 tions. These last also indicate a parallax to the star b. None of the stars appear to have a large proper motion. 8 deals in the same way with observations of the fainter stars, and catalogue of all the stars of the cluster. This is followed by two charts, one of the brighter stars and the plan of triangnlation, the other of the whole cluster. This brief analysis will give an idea of the contents of this extremely thorough paper, which will take its place beside the other researches of the author in the same field. They are all models of what such investigations should be, and leave nothing to be desired in methods of observation or reduction, in the accuracy of the final results reached (which are always adequate to the purpose in hand), and, finally, are excellent examples of the literary style and clearness appro- priate to such memoirs. NEW STARS ; VARIABLE STARS ; RED STARS ; PROPER MO- TIONS, ETC. Dr. Fearnley, Director of the Christiania Observatory, states that a ninth-magnitude star, a = ll h 13 m 31 s , o = + 66 31' 25" (1875), has a proper motion of 3.04" in a great circle, as shown by a comparison of his observations with the Bonn observations of 1S55. This star is 60 distant from the solar apex, and the direction of its motion is such as to indicate that we have really to do with a star near to us, and there- fore suitable for observation for parallax. "The Red Stars : Observations and Catalogue," is the title of a work by J. Birmingham, published in the Transactions of the Royal Irish Academy, Vol. XXVI., Part V. It in- cludes all known red or yellow T ish-red stars, 058 in number, with the positions given for 1880. The catalogue gives the magnitudes (mostly from Argelander) and details concern- ing the color, brightness, and variability, together with an ac- count of spectroscopic observations. Birmingham's observa- tions have been made with a telescope of 4.5 inches aperture, with a power of 53 diameters; and with this instrument stars to the tenth magnitude can be observed, and their color de- termined. Such an aperture has for its minimum visibile 12.5 magnitude on Aro-elander's scale. The observations lead to the conclusion that for variable red stars the red color in gen- eral is increased with a decreasing magnitude. His explana- 8 ANNUAL RECORD OF SCIENCE AND INDUSTRY. tion of this is that the star maybe surrounded by a rotating nebulous ring of different thickness at various parts, so that variations of both color and intensity are the results of ab- sorption. DOUBLK, BINARY, AM) MULTIPLE STARS. Mr. Burnham, of Chicago, has published his ninth catalogue of new double stars discovered with the G-inch refractor. It comprises the discoveries of 1S76 and the first part of 1877. It contains Nos. 453-482, i. e. thirty stars ; of these, eighteen are closer than 2.11". No. 4 of the publications of the Cincinnati Observatory for 1877 has been received. It gives the measures of 517 double stars. The introduction contains an account of the methods of observing. Positions are measured by placing the objects between parallel wires, and with both forward and backward motions of the tangent screw and distances, so as to eliminate the zero and to make the bisections symmet- rical. The three observers were found to have a personal equation in position-angle, which Professor Stone refers pri- marily to the position of the observer's head. The observa- tions are compared with older series, and the probable errors determined. The colors are noted on a new plan, by using numbers, which allow them to be expressed briefly. This publication of the detailed observations is followed by a volume of il/ecm Results, which is a summary of the pre- ceding work. It is in octavo form, sixty stars on a page, and contains observations on 517 such pairs of stars. On the average, about two observations have been made on each pair, both in position and distance. The various columns have for caption, "Number," "Name," "Epoch," "Position- Angle," "Distance," and " No. of Obs." Many close pairs have been measured, and also many neglected stars are to be found in the list. The Rt ndiconti of the (Italian) Royal Academy of Sciences for May, 1*77, contains a memoir by Signor A. Nobile on the trapezium of Orion (^ 748). The instrument employed was a refractor of 0.14" 1 (5.51 inches) aperture. The method of observation employed was that invented by Nobile, and previously described by him. We possess previous determi- nations of tin- relative positions of these stars by W. Struve ASTRONOMY. 9 and by Liaponoff. A comparison of the previous measures of distance with Nobile's indicates no motion. From the com- parison of angles he concludes a probable revolution of stars B, C, and D about A, so as to increase the angle. From this it is inferred that the four stars of the trapezium are phys- ically connected with each other. Professor Hall, of Washington, has observed the six stars in the trapezium of Orion during two years, the different combinations of the angles and distances of these stars bein^ measured first with bright wires in a dark field, and again with dark wires in a bright field. Each angle and distance has been measured on at least six nights by each method. Professor Holden has made a discussion and an adjustment of these measurements by the method of least squares, from which it appears that these six stars are probably physically connected, as supposed by Xobile and others. Observations of the double stars, selected by Mr. Otto Struve, Director of the Imperial Observatory at Pulkova, for determining the personal errors of various astronomers, have been made by Professor Hall, at Washington. This list contains thirty stars, and on an average each star has been observed on six nights. Professor Stone, of Cincinnati, is also observing this list, as well as Professor Winnecke, of Stras- burg, Baron Dembowski, etc. Mr. Burnham, of Chicago, quotes Struve's measures of 2 547, which are (1831) p = 344.3, s 4. 25", and notes measures of his own (1S7S) p=. 9.1, s = 2.46". This appears to be in rapid motion. Mr. Burnham has just sent to the Royal Astronomical So- ciety, for publication, his double-star observations of 1877-78. These comprise: I. A catalogue of 251 new double stars, with measures; II. Micrometrical measures of 500 double stars. Of the 251 new double stars, 75 pairs are less than 1" distant, and 59 pairs are distant from 1" to 2". Over 1400 micro- metrical measures have been made, each of 5 angles of posi- tion and 3 measures of double distance. This great labor was entirely one of love, and the observations were all made after a day spent in business occupations. Considered in this way, the number of measures becomes as remarkable as their excellence. A 2 10 ANNUAL RECORD OF SCIENCE AND INDUSTRY. STAR CATALOGUES AND MAPS. At the Stockholm meeting of the German Astronomical Society, reports of the progress of the zone observations were received. The Fundamental Catalogue, which is based on Pulkova observations (ISC 1-72), will appear during 1878. The observations on which it is founded will first be printed, and the Catalogue will follow. In the Nikolaief zone ( 2to+l) 1015 observations have been made. The Leipsic zone (10-15) is approaching com- pletion. The zone (25-30) undertaken at Cambridge (Eng- land) reports: Total No. of stars to be observed 10,299 ' ; " " " still unobserved 2,2. r >3 " " " " observed once 2.817 " " " " " twice 2,178 " " " " " three or more times. ... 8,55G The reductions are i'l a forward state. The observations of the Leyden zone (30-35) are finished, except about 150 observations, to complete imperfect positions. There were 4300 observations printed in the Leyden Observations, Vol. V.; 2250 more are completely reduced; for 2400 the reduc- tion is begun, and only 900 were untouched. The Bonn zone (40-50). Up to the present time 29,939 stars have been observed by three observers. The Harvard College zone (50-55) contains 8317 stars, of which 2014 have not yet been twice observed. Many of these have been observed once. The Ilelsingfors zone (55-65) will be continued by Dr. Kriiger, at Gotha, with the same instrument as before, which has been lent for the purpose by the Ilelsingfors University. The Christiania zone (65-70) contains 3880 stars, of which 10,744 observations have been made. Two thirds of the observations are completely reduced. The printing was begun during 1878. In the Dorpat zone (70 - 75) 2180 stars have been ob- Berved twice, and 312 once, since August, 1876. The right ascensions are nearly completely reduced. Dr. C. Powalky has reduced all of Lacaille's observations of stars (about 400 in number) taken with the altitude in- struments both at the Cape of Good Hope and at Paris. By introducing new values of the latitude, refraction, and cor- ASTRONOMY. 11 rections for the division errors of the instruments, he has been able to bring about excellent agreement between the Paris and Cape observations with both sextant and sector. The results appear to be comparable in precision with Brad- ley's observations. The epoch chosen is 1750.0. Dr. Schrader, of the O'Gyalla Observatory, Hungary, has published a list and maps of all stars visible in northern lat- itudes from the first to the fifth magnitude. There are five charts in all one polar chart and four others, equatorial charts so divided that in each season of the year (as spring, etc.), only one of these, or at the most two, will be needed. This is a convenience in observations of meteors, and in other ways. The maps have a peculiarity which is new, we be- lieve. The sizes of the circles which represent stars of the various magnitudes are proportioned to the absolute amount of light received by the eye from the stars themselves. 1S40 stars are mapped. An appendix gives the method of com- puting the orbit of a meteor swarm from observations with tables. A catalogue of the mean places of 750 stars for 1870.0, from observations made at Kremsmiinster by P. G. Strasser in 1864-74, has recently appeared. In Vol. XII. of the Mem- oirs of the R. A. S. (1838), a catalogue of 208 stars observed at Kremsmiinster appeared ; and a series of 560 stars, observed about 1840, has been reduced by Reslhuber, but not yet pub- lished. * The maps to the uranometry of the southern heavens, made by Gould and his assistants at Cordoba, have been prepared at Bien & Co.'s, in New York. They are lithographed, and each map will be about half the size of the maps to the Durchrnusterung. Dr. Loewy,of Paris, has presented to the French Academy of Sciences a catalogue of 521 moon-culminating stars. The places of these depend upon observations made at the ob- servatory of the Bureau of Longitudes with portable instru- ments. The Bureau has just completed the determination of the telegraphic longitudes of Neuchatel, Geneva, and Ly- ons. It will shortlv undertake the determination of the Ion- gitude of Lisbon, in aid of the American determination of the longitude of Rio Janeiro just completed by Lieut.-Comman- der Green, U.S.N. 12 ANNUAL RECOKD OF SCIENCE AND INDUSTRY. The Hydrographic Office has published "An Observing List of Stars Selected for the Determination of Time in the Southern Hemisphere." This is a list of 408 polar and clock stare, nearly equally distributed throughout the twenty-four hours. The approximate right ascensions and declinations are given (right ascension to the nearest second, declination to nearest 0.1'), with a reference to one authority for each place. It is for use in the longitude expedition under Lieut.-Com- mander Green, U.S.N. THE SUN. Dr. Dreyer calls attention, in Nature^ to a probable obser- vation of the solar corona A.D. 1030, August 31, and to the fact that Plutarch noticed the faint light round the sun dur- ing a total eclipse. Colonel Tennant, R.E., has published two accounts of as- tronomical expeditions in India. The first is a "Report on the Observations of the Total Eclipse of the Sun December 11-12, 1871 ;" the second, "Report on the Preparations for and Observations of the Transit of Venus as seen at Rourkee and Lahore December 8, 1874." The Report of Messrs. Lockyer and Schuster on the Total Solar Eclipse of 1875 has just been published in the Philo- sophical Transactions of the Royal Society. Bad weather prevented some of the most important plans from being car- ried out. Mr. Downing, of Greenwich, has a note on the probable errors in transit observations of the sun, discriminating the results for the two limbs. He comes to the conclusion that for experienced observers the probable accidental error for the two limbs is the same, w T hile for inexperienced observers the second limb is more uniformly observed. An observer of experience has been sent by the English government to India to arrange for the founding of an ob- Bervatory for the purpose of taking daily photographs of the sun. This is on account of the recent famine in India, and the supposititious connection between sun-spots and famines, which the government seems to consider of sufficient inter- est to go to some expense in order to test it. This is in some sense a reversion to Sir William Herschel's supposed con- nection between sun-spot frequency and the price of wheat. ASTRONOMY. 13 The chief signal-officer of the army has proposed to the various observatories of this country, both public and pri- vate, to co-operate in physical observations of the sun. Ev- ery phenomenon of interest should be registered, whether re- lating to spots, faculae, or protuberances, etc. Each observ- atory that is willing to take up any special field, or that al- ready occupies such a field, is requested to give its results, or such part of them as it is willing to give, to the Signal Bureau for record in its Monthly Weather Eeview. Thus a prompt publication is secured. In response to this invita- tion, a record of the number of spots daily observed on the sun's disk is prepared by Mr. D. P. Todd, of Washington. It is to be hoped that a regular series of photographic records of sun-spots can be made by some one or more observato- ries in the East, and by at least one on the western coast. In order to render such observations of the sun complete, the establishment of these stations and one in Japan is required. Sun-spots continue to be observed photographically at Greenwich, Paris, Moscow, Toulouse, Kasan, Vassar College, and are observed visually at Madrid, Oxford, Berlin, Zurich, Leipsic, and Potsdam. Protuberances are observed at Palermo, Rome, Greenwich, Moscow, O'Gyalla, Potsdam, etc. Professor Langley, of Allegheny Observatory, and Dr. Huo-rrins, of London, some years as;o described the granular surface of the sun's photosphere. Their division of the brighter aggregations of the surface was (successively as to size), first, cloud-like forms, perceptible to telescopes of ordi- nary power ; second, " rice-grains," or nodules, of which such forms are composed, the rice-grains being perceptible with higher powers and good definition ; third, granules compos- ing the rice-grains. The discovery of the granules has been independently made by the photographic researches of M. Janssen, who has succeeded in obtaining photographs of the sun with only a( / uo of a second exposure. These were pro- cured with lenses of long focus, and a slow development of the image. The "willow-leaves" or "rice-grains" of pre- vious observers appear in these photographs only as occa- sional ao-oTeo-ations. The main feature is an abundant gran- ulation. The forms of the oranules are sufficientlv defined 14 ANNUAL RECORD OF SCIENCE AND INDUSTRY. for stud}-. They appear to be generally of a spherical shape, and it is noticeable that larger grains seemed to be formed of aggregations of smaller ones, the lesser grains being most evidently spherical. An interesting account of one of Jans- Ben's largest positives has been contributed to the American Jow-nal of Science for April, 1878, by Professor Langley. In the Annuaire of the Bureau of Longitude for 1878 (p. G89), M. Janssen gives a detailed account of his discovery of the reticulated arrangement of the solar photosphere. The paper is accompanied by a photograph of the appearances described, which is enlarged threefold. M. Janssen says that photographs less than 4 inches in diameter cannot satisfac- torily show such details. The chief obstacle to the produc- tion of photographs of the sun which should show the details of the photosphere has hitherto been the photographic irra- diation. As the granulations of the solar surface are in gen- eral not greatly larger than l" or 2", the irradiation, which sometimes is 20" or more, may completely obscure their char- acteristics. This difficulty M. Janssen has overcome by en- larorinor the ima^e and shortening the time of exposure. In this way the irradiation is diminished as the diameters increase, the dimensions of the details are increased, and " the imperfections of the sensitive plate have less relative importance." [This last advantage certainly holds good only between limits.] Again, M. Janssen has noted that in short exposures the photographic spectrum is almost monochromatic. In this way it differs greatly from the visible spectrum, and to the advantage of the former for this special purpose. The pure- ly photographic difficulties are immensely augmented, how- ever; but these have been surmounted by the care and per- severance of M. Janssen and his assistant M. Anents. The diameters of the solar photograrns have since 1874 been suc- cessively increased to 4.7, 5.9, 7.9, and 11.8 inches. The fo- cal adjustment varies greatly with the season, and even with the time of day. The exposure is equal over all parts of the sin race. In summer this exposure for the largest photo- grams is less than 0.0005 s . The development of the pictures is very Blow. These pictures show that "the solar surface is covered with a line granulation. The forms and the dimen- sions of these elements are very various. They vary in size ASTRONOMY. 15 from 0.3" or 0.4" to 3" or 4". Their forms are generally cir- cles or ellipses, but these forms are sometimes greatly al- tered. This granulation is apparently spread equally all over the disk. The brilliancy of these points is very varia- ble, and they appear to be situated at different depths be- low the photosphere : the most luminous particles, those to which the solar light is chiefly due, occupy only a small frac- tion of the solar surface." The most remarkable feature, however, is "the reticulated arrangement of the parts of the photosphere." "The photograms show that the constitution of the photosphere is not uniform throughout, but that it is divided in a series of figures more or less distant from each other, and having each a special constitution. These figures have, in general, rounded contours, but these are often al- most rectilinear, thus forming polygons. The dimensions of these figures are very variable ; some are even 1' in diameter (over 25,000 miles)." " Between these figures the grains are sharply defined, but in their interior they are almost effaced, and run together as if by some force." These phenomena can be best understood by a reference to the figures of M. Janssen. SOLAE ECLIPSES. The best general account of the principal results of the to- tal eclipse of July 29, 1878, which has yet appeared, was written by Professor C. A. Young in the New York Times of August 1G. A portion of this is given below : "As regards the physics of the sun and the corona, the principal and most important result of all the observations bearing upon this subject is to demonstrate a decided sym- pathy and connection between the condition of the sun's vis- ible surface, as indicated by the number and character of the sun's spots, and the constitution of the corona. "At the present time the sun's spots are at their mini- mum; whole months have passed without the appearance of a single one. The chromosphere, or colored envelope of hy- drogen and other gases which immediately surrounds the sun, has also been correspondently quiescent, and the so- called 'prominences' have been few and small. Of course, it was a question of interest whether the corona also would show a corresponding difference of condition from that indi- cated in 1869 and the later eclipses, when the sun's surface 1 G ANNUAL RECORD OF SCIENCE AND INDUSTRY. was in full activity, and the question has received an em- phatic and affirmative answer. "As to the brightness of the corona at the recent eclipse, there is considerable difference of opinion. The writer, with, lie thinks, a large majority of those who also saw the eclipse of 18G9, is strongly of the impression that in 1869 the corona, though perhaps less extensive, was many times more brilliant, while the corona in 1870 seemed to him intermediate be- tween those of 1809 and 1878. Some of the best observers, however, are of quite the contrary opinion. " While, however, there may be room to question the con- clusion that the corona this year was uncommonly faint, there can be no question that its spectrum was profoundly modified. "The bright lines which come from its gaseous constitu- ents were conspicuous in 1869 and in all the subsequent eclipses until the present one; but this year they were so faint as to be seen by only a few of the observers, while the great majority missed them entirely, seeing only a continu- ous spectrum. This w 7 as especially remarkable in the case of the green corona line (known as ' 1474' from its position upon Kirchhoff's map of the solar spectrum). Many observers saw it plainly just at the beginning and end of totality, but during the middle of the eclipse nearly all entirely lost sight of it. That it was really present all the time, however, though faint, is proved by the observations of Professor Eastman, Mr. Thomas, and the writer, the first of whom traced it all around the sun to a distance of from 10' to 20', going twice over the ground, and keeping it in sight all the time. "With the hydrogen lines the case was similar; the writer had one or other of them in the field continually, and they never quite disappeared, though at times very faint. " Of course, the slitless spectroscopes, both ocular and pho- tographic, from which so much had been expected, failed to give any satisfactory results. In 1871, when the instruments Merc first used, the observers saw a series of colored images of the corona. Mv. Lockyer, for instance, saw four such im- ages one icd, one green, one blue, and one violet. This year nothing oft lie kind appeared. At the moment, indeed, when totality began, there was an exquisite exhibition, first of the darkness of the solar spectrum, and then for an instant of a multitude of bright-colored segments the spectrum of the ASTRONOMY. 17 chromosphere; but when the moon had covered the chromo- sphere, there was only a disappointing continuous band of color, unmarked by rings of any kind. "Those, also, who were looking for new bright lines in the corona spectrum were equally unsuccessful, whether they employed the ordinary spectroscope or worked by photogra- phy. Some of the observers, the writer among others, used a so-called 'fluorescent eye-piece,' which brings the other- wise invisible light beyond the extreme violet end of the spectrum within the range of the human eye by the action of a film of fluorescent liquid (sesculia solution) enclosed be- tween thin plates of glass. But, although before totality the apparatus worked perfectly, disclosing to the eye dark lines innumerable in the portion of the spectrum invisible without its aid, after the darkness came on it failed to show a single bright line. The most carefully prepared and sensitive pho- tographic apparatus succeeded no better, except that Dr. Draper, Mr. Lockyer, and one or two others perhaps, did ob- tain, by means of a slitless spectroscope, an impression of a faint continuous spectrum in the ultra violet, without rings or markings of any kind. Evidently no lines existed to see or photograph on this occasion. " One or two observations were made of some interest in their relation to previous work. Professor Rockwood, of the Princeton party, using a double-barrelled slitless spectro- scope, observed at the beginning of totality a bright-red line in the chromosphere spectrum very near to B. This explains an observation of Mr. Pogson in 1868, who then insisted that lie saw B reversed in the spectrum of a prominence; but as all the other observers had C instead of B, his record was generally regarded as a mistake. "The line is probably one well known to solar spectro- scopists as 534 of Kirchhoff's scale a line exceedingly diffi- cult to see in the spectrum of the chromosphere under ordi- nary circumstances, but still invariably present. Its conspic- uousness in Professor Rockwood's instrument is a matter of some surprise; but there could be no mistake, as C was even more brilliantly conspicuous at the same time. What the substance which causes it may be is quite unknown. Like the so-called D 3 line, it has no corresponding dark line in the solar spectrum. 18 ANNUAL RECORD OF SCIENCE AND INDUSTRY. " The same observer, and the writer also, saw both II lines (calcium) brightly reversed in the spectrum of the chromo- sphere; thus confirming observations made six years ago at Sherman, but never corroborated since, except by the photo- graphic spectrum obtained by the Siam expedition in 1875. "The exquisite reversal of the dark Fraunhofer lines at the moment of totality was seen by many of the observers. One observer, at least (and we believe some others), Profess- or Barker, at Rawlins, was able to confirm Janssen's observa- tion in 1871 by seeing the principal dark Fraunhofer lines in the corona spectrum, thus showing that a considerable percentage of the coronal radiance is mere reflected sunlight. The dark lines were, however, so faint as to be seen by very few, and this shows equally clearly, we think, that the parti- cles which reflected the sunlight are themselves also self-lu- minous, as, of course, they ought to be so near the sun. "A great deal of attention has been paid to the polariza- tion of the coronal light in past eclipses, and while on the whole there has been an overwhelming weight of evidence in favor of radial polarization, yet at every eclipse some ob- server of reputation has obtained anomalous results quite at variance with all the others. This year Dr. Hastings, of Bal- timore, comes out with strong tangential polarization as his result. The rest of the observers Wright, Ran yard, Iiark- ness, and others are emphatic and clear in their contrary conclusion. "Experiments with the tasimeter, or new heat-measurer, of Mr. Edison showed, as was ascertained many years ago, that the heat of the corona is quite sensible. With a thermopile attached to a peculiarly arranged spectroscope, Mr. Ander- son, of the Princeton party, obtained a doubtful result, which may indicate a bright heat-line in that part of the chromo- sphere spectrum below the red. "It has been represented that the results of this eclipse require a fundamental reconstruction of the theories hitherto held regarding the constitution of the corona. This is, how- ever, an entire misapprehension. The same constituents ap- pear in the corona as hitherto, only in altered proportions, as might have been, and was, expected by students of solar physics. In 18G9, 1870, and 1871 the gaseous elements of the corona the hydrogen and '1474 stuff,' whatever that ASTRONOMY. 19 may be were in such quantity and condition, and rose so high above the solar surface that their lines were conspicu- ous in the coronal spectrum, and attracted the attention of observers far more forcibly than the feeble continuous spec- trum of the light emitted from, and reflected by, the minute solid or liquid particles which also constitute an essential element of the corona. At present the condition is reversed. The gases are either too small in quantity or too cool to be conspicuous. The lesson, and it is an important one, is sim- ply, as has been said, that, to a certain extent, the corona sympathizes with the sun-spots. " It certainly looks probable, also, that while the gaseous elements of the corona are strictly solar, the non -gaseous matter the coronal dust or haze is of extraneous and very likely meteoric origin. At any rate, the extent of the corona was certainly not less than on former occasions, whatever may have been the case with its brightness. In fact, it has never been traced quite so far from the sun before, as this time by Langley and Newcomb, who followed it out for 6 along the ecliptic, a success partly, of course, due to the clearness of the air at their elevated stations. Now, this is quite consistent with the theory that meteor streams furnish the hazy matter of the coronal envelope, since, so far as we can judge, they have nothing to do with sun-spots. " A very interesting problem relates to the effect of solar forces upon this meteoric matter, if such it really be, and the material for the study is furnished in rich abundance by the numerous drawings made by Langley, Abbe, Penrose, Boss, and others, and by the photographs, which in excellence and number excel those obtained on any previous occasion. Among; the best which we have seen are the mao*nificent se- ries made by Rogers at La Junta, those of Draper at Raw- lins, and those of the Princeton party at Denver; undoubt- edly there are others of at least equal excellence. "To sum up: the eclipse of 1878 has probably added a new planet to the system, and has rendered it likely that the unknown cause, whatever it may be, which produces the pe- riodical sun-spots at intervals of about eleven years, also af- fects the coronal atmosphere of the sun. "The result of the late eclipse goes to show such a peri- odical change in the state of the solar atmosphere as might 20 ANNUAL RECORD OF SCIENCE AND INDUSTRY. very possibly produce a sensible effect upon the earth ; whether it does or not is a question which can be settled only by a careful and systematic investigation of the facts." The detailed reports of the various parties sent out by the Naval Observatory have not yet been printed. The follow- ing abstract of their principal work is taken from the Re- port of the Secretary of the Navy for 1878. It was seen that in order to obtain thoroughly satisfactory photographs of the corona, it would be necessary to use far more powerful apparatus than had been employed hereto- fore, and it was proposed by Professor Harkness to con- struct two equatorial cameras of six inches aperture and thirty-six inches focus. This plan was adopted, the objec- tives being furnished by Dallmeyer, of London. Two of the Tran sit- of- Venus 5-inch telescopes were removed from their equatorial mountings, and the cameras were substi- tuted in their places. In this way two very serviceable in- struments were obtained which were subsequently used by the parties of Professors Hall and Harkness. It was finally decided to adopt dry plates, and Mr. Jos. A. Rogers kindly furnished the observatory with some of his own manufact- ure. The results subsequently obtained with them upon the corona prove that there is every reason to be thankful that his generous offer was accepted. As the liberal appropriation made by Congress enabled the observatory to fit out quite a number of parties, the co-operation of all the best-known astronomers in the coun- try was solicited, and they responded heartily. While the observatory was able to assist them both pecuniarily and by the loan of instruments, they were left entirely free to plan their own observations; thus securing; a wide rano-e of in- vestigation. The final arrangement of the parties, and the work accomplished by each, were briefly as follows : The party under charge of Professor Hall was stationed at La Junta, Col. The principal results of the work of this party were : 1. Professor Hall made an unsuccessful search for Vulcan with a 5-inch Chirk equatorial, magnifying power one hun- dred and fifty diameters. The space south of and following the sun was swept over, keeping near the ecliptic and sweep- ing about 10 east of the sun. ASTRONOMY 21 2. Mr. Wheeler made an unsuccessful search for Vulcan with a 5-inch Clark telescope, magnifying one hundred and fifty diameters, and mounted as an alt-azimuth. The space swept over was below and preceding the sun, where Profess- ors Watson and Swift discovered Vulcan. 3. Mr. J. A. Rogers made five photographs of the corona. The exposures were 3, 5, 10, GO, and 20 seconds. The image of the moon was --$ of an inch in diameter. As the expos- ures were increased, more and more of the corona w T as shown, and the longest exposure gave a corona twenty minutes of arc in extent each side of the sun. These photographs show a great amount of detail, and in connection with those of other parties will probably give more information in regard to the minute structure and ex- tent of the corona than has yet been obtained from photo- graphs. Professor A. W. Wright determined the plane of polariza- tion of the corona, and the percentage of polarized light pres- ent, and took two photographs. Dr. Thorpe determined the magnetic elements of La Jun- ta, and photographed the corona. The party under direction of Professor Harkness was sta- tioned at Creston, Wyoming Territory. Professor Harkness, assisted by Lieutenant E. W. Sturdy, searched the violet and ultra-violet portions of the coronal spectrum for bright lines, but found none. Mr. Alvan G. Clark and Mr. A. "N. Skinner managed the equatorial camera, and obtained six photographs of the coro- na, which are thought to be at least as extensive and as rich in detail as any ever taken. The exposures were, respective- ly, 3, 15, 30, 60, 8, and 5 seconds. Professor Otis II. Robinson used the polariscopic camera, and obtained four photographs which distinctly show the polarization of the corona. They are now in the hands of Professor A. W. Wright, who is making a special study of that subject. The party under direction of Professor Eastman selected as an observing-station the town of West Las Animas, Col. Professor Eastman observed contacts, and, with a single- prism spectroscope attached to a 5-inch equatorial, traced the limit of the substance in the corona which gives the 22 ANNUAL RECORD OF SCIENCE AND INDUSTRY. bright line "1474" in the green portion of the spectrum, on the north, east, south, and west limbs of the sun. The exist- ence of this line was demonstrated to a distance from the sun's limb equal to about four tenths of the solar diameter, and the limit was about the same in the four different direc- tions. Professor Boss determined the latitude and longitude of the station, observed contacts, and during totality devoted himself to the study of the details of the structure of the corona. Professor Pritchett observed contacts, and during totality devoted a portion of his time to an unsuccessful search for Vulcan, and the remainder to a study of the solar promi- nences, and one or two portions of the corona. Assistant Paul observed contacts, and during totality sketched the outline of the corona projected on a finely ground glass plate in the focus of a telescope of 48.5-inch focus, with an objective of 3.5 inches. Mr. H. S. Pritchett observed contacts, and during totality pointed the telescope which carried Professor Eastman's spectroscope. The party under Professor Holclen was stationed at Cen- tral City, Col. The work done was as follows : Professor Holden made an unsuccessful search for Vulcan, and a sketch of the corona. Dr. C. S. Hastings made six independent determinations of the plane of polarization of the coronal light. Professor E. W. Bass made a minute examination of one half of the corona, and observed the four contacts. Lieutenant S. W. Very, U.S.N. , determined the latitude and longitude of Central City, and assisted Dr. Hastings during totality by pointing his telescope. Mr. J. E. Keeler made a crayon drawing of the corona. Mr. C. IT. Rockwell made a sketch of the corona, and noted time for Professor Bass. Mr. Peers, of Central City, took a photograph of the co- rona. This photograph is noteworthy, as it gives more of the outer corona than any other, and is a valuable supple- ment to the photographs of Professors Hall and Harkness, which give so much detail in the inner corona. (The outer corona is shown over 60' on each side of the sun.) ASTKONOMY. 23 The party under Professor S. Newcomb was stationed at Separation, Wyoming. This party observed contacts and exposed a large number of (dry) photographic plates in a photoheliograph. When these plates came to be developed, no image of the sun was seen. The plates were certainly sensitive, and the cause of the failure is unknown. Commander W.T. Sampson, U.S.N"., who observed the eclipse at Separation with Professor Newconib, describes briefly his examination of the spectrum of the corona in The American Journal of Science for November. The result he sums up as follows : " The conclusion forces itself upon my mind that the light of the corona is not all reflected light. Several considerations lead to this conclusion. Until this eclipse, no observer has ever seen the dark lines in the spectrum of the corona except M. Janssen, who reported dark lines, notably D, in 1871, but much more difficult to see than the bright lines. Several observers during the recent eclipse failed to see the dark lines, though they looked for them carefully. While I do not question the results of observers who report the presence of dark lines, I think all the observations taken together show that the continuous spectrum of the corona is not the spectrum of the sun. Aside from this, Professor Ar- thur W. Wright made measurements of the polarization of the light of the corona the first time, I think, it has been at- tempted and has found the polarization to be but a small percentage of the whole light emitted. Although all re- flected light does not reach us as polarized light, yet I think the small percentage of polarization, taken with the faint- ness of the dark lines, indicates that the corona is to a considerable extent self-luminous. The meteoric dust not only reflects the sun's light, but it is continually shower- ing upon the sun, and in its passage through its atmosphere is rendered incandescent. No photographs of the spec- trum of the corona can probably throw any light upon the matter." A party consisting of Professors S. P. and J. W. Langley occupied the summit of Pike's Peak. They were engaged in photometric determinations of the light of the coronn, etc., and secured valuable drawings ; and Professor S. P. Langley was able to trace the corona for several degrees on 24 ANNUAL RECORD OF SCIENCE AND INDUSTRY. each side of the sun, and to see it after the reappearance of the sun. Mr. G. W. Hill made a drawing of the corona at Denver, Col. Professor O. Stone and Mr. W. Upton observed the eclipse a few miles east of Denver. Contact and other observations were secured. Messrs. L. and G. IT. Trouvelot observed at Creston, and a tine pastel drawing of the corona has been received from them. Mr. D. P. Todd, of the Nautical Almanac Office, was sta- tioned at Dallas, Texas, and, in spite of cloudy weather, ob- served contacts. He also secured a number of observations of the duration of totality from volunteer observers stationed near the limits of total eclipse. The discovery of Vulcan by Professor Watson is men- tioned elsewhere. TRANSIT OF MERCURY, MAY G, 1878. The transit of Mercury w r as observed by Professor Hall at Washington. Seventy-two photographs of the planet, when on the disk of the sun, were made at Washington by Mr. Jo- seph A. Rogers with one of the photoheliographs used in pho- tographing the transit of Venus in December, 1874. Professor Harkness went to Austin, Texas, to observe this transit. Although the first half of the transit was lost in clouds, he was favored with a clear sky and a steady atmos- phere during the latter half, and succeeded in making twen- ty-five measures of the polar diameter of Mercury, the same number of measures of its equatorial diameter, excellent de- terminations of the instants of third and fourth contact, and a very satisfactory observation of the physical phenomena attend in 2f these contacts. The transit was observed by Professor Eastman with the 9.6-inch equatorial at the Naval Observatory ; and by As- sistant Astronomers Frisby and Skinner with smaller equa- torials. Professor Eastman observed the second, third, and fourth contacts, made several series of measures of the di- ameter o Mercury, and made a careful study of the physical phenomena at the time of contacts. Assistant Astronomers Frisby and Skinner observed contacts. ASTRONOMY". 25 Professor Holden, in connection with Dr. Draper at Has- tings-on-the-Hndson, observed the third and fourth contacts, and secured nineteen good photographs. Assistant H. M.Paul observed the transit at Hanover, N.H. Professor James C.Watson and Professor E. C. Pickering photographed the transit of Mercury with instruments fur- nished them by the Naval Observatory. Professor Watson exposed seventy-two plates, but, owing to bad weather, Pro- fessor Pickering exposed successfully only twenty-six. The plates were returned to the Naval Observatory and there developed. The London Academy, May 18, states that cloudy weath- er prevailed over England during the transit of Mercury on May 6, but that Scotch observers were more successful. From the Observatory the following is extracted: "In ad- dition to the observations given in the report of the meeting of the R. A. S., reports have been received from a number of observers abroad. M. Janssen, at Meudon, was able to see Mercury outside the sun's disk before external contact; and by means of the spectroscope he succeeded in establishing the existence of an atmosphere round the planet, and its constitu- tion. He also obtained some photographs, of which two are excellent. Captain Mouchez and MM. Henry at the Paris Observatory observed internal contact, though the observa- tion was bad, owing to cloud, as was also the case at Algiers and Bordeaux. "At Toulouse M. Perrotin observed internal contact through cloud so dense that a dark glass was not used. Under these circumstances, he remarked a dark aureole or penumbra round the planet, but this disappeared when the light became too bright. "The French expedition to Ogden, Utah, was perfectly suc- cessful, seventy-eight photographs of the transit having been taken by MM. Andre and Angot, as well as observations of contact. Satisfactory observations and photographs were also taken at the observatory of West Point, N. Y. "The transit was also observed in Spain, at San Fernando and Cadiz. At the latter place M. Arcimis records that no arc of light was seen before internal contact, either outside the sun or round the part of the planet's limb on the sun. At inter- nal contact the planet assumed a balloon or pear shape, and B 2G ANNUAL RECORD OF SCIENCE AND INDUSTRY. for a long time after no ring was seen round the planet. About an hour and a half alter ingress, however, a dark rino-, not so black as the planet, and about 8" or 10" broad, was seen, the sky being then quite clear." Mr. Talmage, of Leyton, observed a luminous ring about Mercury, which was very well defined. lie had, however, only a few seconds of clear weather. In this country it was extensively observed, and many photographs were made. These are now being measured at the Naval Observatory, Washington. Professor Langley, at Pittsburgh, observed the transit of Mercury under favorable conditions. The planet was seen outside the sun about half a minute before first contact, the whole disk being seen. Haze prevented similar observations at egress. No bright point or annulus was seen. The dark- est part of the planet was the centre, the edges being less gray, but the planet was certainly not black. Photometric measures of the absolute amount of light from Mercury were attempted, but Professor Langley interprets the results as measures of the minimum effect to be assigned to the earth's atmosphere in inflecting the solar light. The observations of contact published up to the present time agree closely with the predicted times based on Lever- rier's tables, the general accuracy of which is thus supported. TRANSIT OF VENUS AND SOLAR PARALLAX. The publication of the results of the French Transit-of- Ve- nus reductions has been delayed through the illness of the editor, M. Puiseaux. The results of the eye observations have been deduced, however, and harmonize well, being between 8.82" and 8.88" from pairs of stations, and the general result will not be far from 8.85". The difference between this and the English result, 8.77", is marked. The French photograph- ic results are not yet published. A somewhat unexpected result is obtained by the reduc- tions of the British observations on the last transit of Venus. The data used are the eye observations (telescopic) in Egypt, Honolulu, New Zealand, Rodriguez, and Kerguelen. The photographic observations, of course, were not combined with these, and there arc also eye observations taken in India and Australia that may be utilized; but it is not believed that any ASTRONOMY. 27 great change in the result will be effected by the figures ob- tained from the latter source. The new British calculations give for the value of the sun's parallax 8.76", with a proba- ble error of 0.013". This corresponds to a distance for the sun of 93,300,000 miles, with a probable error of 140,000 miles. The British photographs of the transit of Venus have been twice measured, and are discussed by Captain Tupman. His conclusions are that the English method was fundamentally wrong (as, indeed, was predicted), and the two results (8.25" and 8.08") are of no value, and must be rejected. Lord Lindsay has published the second volume of the An- nals of the Dun-Echt Observatory a quarto volume of 212 pages. It contains the determination of the solar parallax by observations of J~uno, and a description (with plates) of the heliometer employed. The method employed is the de- termination of the diurnal parallax, and this experiment was tried to determine the advantages or disadvantages of the method. The authors (Lord Lindsay and Mr. D. Gill) think that this method has been shown to be one of the very best, and the resulting solar parallax 8.77"0.041" is regarded as a close approximation, to be subsequently corrected by sim- ilar observations of Mars and asteroids which have been made by Mr. Gill at Ascension Island. The description of the he- liometer, with the investigation of its constants, is very full, and will serve as a manual for similar investigations. It is concluded that it is possible with this instrument to deter- mine the distance of a minor planet relative to two stars with a probable error of less than 0.1". THE DISCOVERY OF VULCAN. The reports of Professor James C. Watson, of Ann Arbor, Mich., and Mr. Lewis Swift, of Rochester, on their discovery of a new star or stars during the eclipse are given below in the form of letters to the Superintendent of the Naval Ob- servatory, Washington. Subsequent letters give changes in matters of detail, but the most important facts are given be- low. Professor Watson says : "I am now able to give you more precise information in reference to my observations of a supposed new planet dur- ing the recent total eclipse of the sun. . . . Before the com- mencement of the eclipse, the adjustment of the equatorial 28 ANNUAL RECORD OF SCIENCE AND INDUSTRY. had been attended to, so that the error to be feared on this account will be very small. A few minutes before the total phase, I swept over regions east and west of the sun from eight to fifteen degrees distant; but I did not see any star. Immediately after the totality, I began sweeps east and west, extending about eight degrees from the sun. The first sweeps were towards the east. On the fifth sweep I found between the sun and Theta Cancri, and farther south, a star of the 4% magnitude, as estimated at the instant, which immediately attracted my attention on account of its general appearance. I had committed to memory the relative positions of the stars in the neighborhood of the sun, and I had placed the chart of the region conveniently before me for ready reference when- ever required. There was a fainter star west and north of T/ieta Cancri, as shown on the chart, and I could not be sure of the place without an actual measurement. The object which I had in the field shone with an intensely ruddy light, and it certainly had a disk larger than the spurious disk of a star. . . . Having made the record, I placed my eye again at the telescope, and saw that there had been no disturbance of its position. I noticed, further, that the object in the field did not present any elongation, such as might be expected if it were a comet in that position. The sweeps were then con- tinued, and I finally brought into the field what I supposed to be Gamma Cancri, although it appeared very much bright- er than Delta Cancri, which I had seen near the sun at the commencement of the search during the totality. I proceed- ed to record its position on the circles. Before this was com- pleted the total phase had ended, and I ran across to where Professor Xewcomb was observing, in hopes of being able to direct his larger telescope, with graduated circles, upon the object first seen before the sunlight would interfere; but he was reading his circles for an object which he had in the field, and his telescope could not be disturbed. Thereupon I returned to my own telescope ; but the sunlight had already become so bright that further observations were impossible, and hence I could not assure myself that a gust of wind had not disturbed the instrument before I had marked the last pointing. . . . The places of the sun were again recorded and verified at suitable intervals, so that the position of the star (which I believe to be an intra-Mereurial planet) can be de- ASTRONOMY. 29 termined relatively to the sun. ... In the brief time allotted it was not practicable to change the eye-piece and observe the star in question under a higher power. Its light was quite red, and, so far as my recollection of its appearance in the telescope will enable me to determine, I am of the opinion that it was situated beyond the sun. . . . " In regard to the star B, which I consider to be the planet sought, there is no uncertainty whatever, beyond the una- voidable errors of the record as made. I consider the place given to be trustworthy. ... I have further observations of contacts, and also some sketches of the corona made by members of my party, which I will send you in due season. Meanwhile, I doubt not that yon will agree with me that the observations above detailed establish the existence of one new star in the vicinity of the sun, and point possibly to the existence of two." Professor Watson is now inclined to believe that both of the new objects seen by him are planets. Mr. Swift's observations were made at Denver. He says : "About one minute after totality I observed two stars, by estimation three degrees southwest of the sun, pointing to- wards the sun, of about the fifth magnitude, or what I esti- mated at the time, as bright through the telescope as Polar- is is to the naked eye. How much allowance ought to be made in estimating magnitudes so close to a totally eclipsed sun I do not know. I saw them three times, and attempted, at the last moment, to get another observation ; but at the critical moment a little cloud passed over the sun, and I has- tened to observe again the sun for the third contact and at- tending phenomena. At each of the observations, by care- ful comparison, they appeared exactly of the same magni- tude, and both as red as Mars. I looked closely for twink- ling, but they were as free from it as the planet Saturn. They both, at the time, seemed to my eye and mind to have a small round disk about like the planet Uranus. Whether the disks were imaginary or real I cannot tell, but every time I saw them (the stars) the disks attracted my atten- tion." Professor Pliny E. Chase writes to the Smithsonian Insti- tution that "Gaillot's orbit for Watson's second intra-Mer- curial planet represents his tenth subsidence-node [f Jupiter ,30 ANNUAL RECORD OF SCIENCE AND INDUSTRY. -=-(2 1)], and gives the ninth verification to his harmonic prediction. Gaillot 0.1803; Chase 0.1826." Till-: PLANETS AND SATELLITES. Jfercury. The principal observations of Mercury arc spoken of under the heading Transits of Mercury. Venus. M. Boutigny has called the attention of the French Academy to the fact that Varro (31 B.C.) spoke of changes in the diameter, color, figure, and path of Venus. The passage referred to is quoted in a work of St. Augustine. Venus has been observed during the last year with the 26- inch Washington equatorial. No markings on the disk were seen, but the illumination of the dark hemisphere was fre- quently noted by several observers. Mars. From the recent discussion by Professor Hall of his observations of the satellites of Mars, we extract the follow- ing : " The planes of the orbits of both satellites are very near- ly coincident with the equator of Mars. The elements of these orbits are determined with tolerable accuracy, except- ing the periodic times, for an accurate determination of which we must wait until the satellites have been observed in an- other opposition. The times that have now been found will serve to carry forward an ephemeris to 1879. In the orbit of Deimos, the value of the eccentricity being small, the posi- tion of the line of apsides is of course uncertain. This eccen- tricity is so small that circular elements of this satellite may be considered as sufficient for the observations. In the case of Phohos, the eccentricity of its orbit has, I think, a real ex- istence. It will be noticed that in the comparison of the observations of PJiobos with the assumed circular elements, every comparison of distance confirms the existence of an eccentricity. It is true that the observations of this satellite were always difficult on account of its closeness to the planet, and also because of the brightness of the planet; and it may be suspected that some systematic error has influenced the result. Such an error would indeed have more influence on the eccentricity of the orbit of the inner satellite than on that of the outer one. But the resulting eccentricity is too large, I think, to be explained in this manner, and I conclude that the orbit of Phobos is really eccentric." The mass of Mars can be determined from the motion of ASTRONOMY. 31 these satellites. "Expressing the mass of the planet in the common unit, we have, from the above values of the elements, the following results : v 1 Deimos: Mass of Mars Phobos: Mass of Mars =^ 3095313 3485 1 3078456 10104' " These results agree so nearly within the limits of their probable errors that I have taken the mean by weights as the final result from the Washington observations. In this way w T e have Mass of Mars=- ; : ." 3003500 3205 The recent report of Professor Pickering, Director of Har- vard College Observatory, states that it has been decided to devote the large refractor chiefly to photometry. In this way a field is taken up which has too long been unoccupied. Besides a great number of photometric observations on dou- ble stars, asteroids, and satellites of the outer planets, the satellites of Mars have been studied. Assuming the albedo, or intrinsic reflecting power of these bodies, to be the same as that of Mars, it is concluded that the diameters are for Deimos (outer satellite) about 6 miles, and for Phobos (inner) about 6.5 miles. Following are some previous values of the mass of Mars which are interesting for comparison with Professor Hall's results : Laplace assumed the mass of Mars to be la4 S 08 -g. Delambre reduced this estimate to tj 54 * ^ -^j. Burckhardt, in 1816, diminished this still further to -^mruTST- By Han- sen and Olufsen, of Sweden, in their solar tables, the esti- mate is S2UUUUU- Leverrier got ^yrnrnro- The spectrum of Mars has been photographed by Dr. Huggins. Professor Hall, of Washington, made, daring the last opposi- tion of Mars, a, large number of measures (thirty-two nights) of the position of the south polar spot of Mars. From all of these he finds for the angle of position of this spot for 1877, September 17.0 G. M. T., 166 22', and for the same epoch the radius of the small circle described by the spot is 5 11'. The various determinations of the south polar dis- 32 ANNUAL KECOHD OF SCIENCE AND INDUSTRY. tance of the spot are: Herschel (1783), 8 8'; Bessel (1830), 8 6'; Madler (1837), 12 0'; Secchi (1857), 17 42'; Linsser (1862), 20 0'; Kaiser (1802), 4 16'; Hall (1877), 5 11'. A similar work lias been clone by Professor Schiaparelli at Mil- an, and he finds for 1877, September 27.0, X = 6 15', Hall's result for this epoch being 5 18'. Professor Hall's observa- tions were of the angle of position of the spot, while Schia- parelli made his own by placing the micrometer wire tan- gent to the limb of the planet at the middle of the spot. A series of the same kind (as yet unpublished) was made at the Dudley Observatory by Professor Boss. Jupiter. The conclusions of Mr. Neison upon the atmos- phere of Jupiter are that it may be regarded as certain that it is physically impossible for Jupiter to have an atmosphere of great depth, unless the temperature of the planet be sup- posed to be many million times hotter than a white heat, or unless the atmosphere is constituted of some substance un- known to us, and widely different from substances familiar to ur.. Saturn. In the Astronomische JVcichrichten y Mr. Marth con- tinues his very complete ephemeris of the five inner satellites of Saturn. He notes the desirability of observations of the conjunctions of Mimas with the ends of the ring, but has overlooked the fact that no satisfactory observations of these phenomena have ever been made. From his own observa- tions at Malta, and the experience at Washington, it is even doubtful if they ever can be made. It may be worth while to note in this place the times of sidereal revolution of the five inner satellites adopted by Marth. They are, Mimas, d. 22 h. 37 m. 8.26 s. ; JJnceladus, 1 d. 8 h. 53 m. C.86 s. ; Tethys, 1 d. 21 h. 18 m. 25.96 s.; Dione, 2 d. 17 h. 41 m. 9.33 s.; Jihea, 4 d. 12 h. 25 m. 11.87 s. M. Tisserand continues in the Comptes JRendus his re- searches on the system of Saturn, and has published the mo- tions of the perisaturnium of each of the five inner satellites. For Mimas this motion is 349 per annum. Tisserand further shows how the mass of the ring itself may be determined, as well as the oblateness of the ball. For this, continued obser- vations of Mimas and Titan arc necessary. "The appearance of the ring of Saturn was carefully ob- served at Washington during the whole opposition, and it ASTKONOMY. 33 was followed until February 11, 18*78. The disappearance of the ring occurred about February 6. The angle of posi- tion of the major axis of the ring was observed on thirty-six nights by Professor Hall, and on twenty-two nights by Pro- fessor Holden. Although at the time of the disappearance of the ring the planet was too near the sun for good obser- vations, yet the whole of these observations indicate that Bessel's elements of the ring are very nearly correct." Professor Hall, of Washington, lias an investigation of the outline of the shadow of a planet projected on any plane first, for the case where the luminous and opaque bodies are both spherical; and, second, where the opaque body is supposed to be an ellipsoid of revolution. The conclusion is that, even in the case of Saturn, which has the most eccentric figure of any of the planets, the outline of the geometric shadow on the plane of the ring is sensibly a right line. The apparent convexity of the bounding line of this shadow towards the centre of Saturn has then to be explained from conditions other than geometrical. M. Souillart, known by his researches on the theory of Jupiter'' 8 satellites, has a paper in the Astronomische Nacli- richten on the shape of the shadow of a planet, and comes to essentially the same conclusions as previously given by Pro- fessor Hall in the same journal. M. Tisserand, of Toulouse, who has lately occupied himself with the system of Saturn,h&s an important note in Compter Rendus on the nature of the ring. Laplace proved in 1787 that even if observation did not show that the ring of Saturn was composed of two or more concentric rings, the theory of gravitation would require this. Tisserand, as the result of the re-examination of the problem, comes to the conclusion that a continuous ring of the dimensions of the real rinse c^ 11 ' not exist in equilibrium. Hence it is divided. In fact, the ring of Saturn has been seen (by Bond, De la Rue, Dawes, etc.) divided into numerous fine concentric rings, just as this condition requires. Uranus and Neptune. The satellites of these planets are followed at the Naval Observatory, Washington. B2 34 ANNUAL KECOKD OF SCIENCE AND INDUSTKY. MINOR PLANETS DISCOVERED IN 1878. Date. No. Name. Discovered by Dis.'.s No. Observatory of Jan. 20 180 Garumna Perrotin 5 Toulouse. Feb. 2 181 Eucharis Cottenot 1 Paris. Feb. 7 182 ? Palisa 12 Pola. Feb. 8 183 V Palisa 13 Pola. Feb. 28 181 Diopeia Palisa 14 Pola. ? 1 85 Eunike Peters 28 Clinton. April 10 186 Celuta Henry ? Paris. April 11 187 v Coggia 2 Marseilles. July 7 188 Menippe Peters 29 Clinton. Sept. 17 189 Phthia Peters 30 Clinton. Sept. 22 190 Ismene Peters 31 Clinton. Sept. 191 Kolga Peters 32 Clinton. i THE MOON. " Lohrmann's Map of the Moon consists of 25 sections on the scale of 37.5 inches to the moon's diameter, or the same scale as Beer and Madler's ' Mappa Selenographia.' They have been engraved at different times on copper-plate, and are in every respect perfectly analogous to the four original sections which were issued in 1824. They have been care- fully edited by the well-known selenographer Heir Julius Schmidt, of the Observatory at Athens, and are a faithful re- production of the original ink maps of Lohrmann, so that in the present map we have an exact representation of the sur- face of the moon as it appeared to Lohrmann during the period 1821-27. On this account, therefore, the map will form a most valuable contribution to selenography. In his capacity of editor, Schmidt has added to the map all the standard names of Beer and Madler. lie has also named a number of additional points." Schmidt's great map of the moon has not reached this country, so far as we know. Professor Newcomb, of Washington, has an important note in Silliman'8 Journal (November) on the mean motion of the moon. It is an abstract of the researches which have been published in full in Wash. Ast. Obs., 1875. lie has made a discussion of all trustworthy recorded ob- servations of the moon before 1750 eclipses and occupa- tions. These materials are : 1. Ancient eclipses (total) of the sun, such as the celebrated ones of Larissa, etc. Professor Newcomb comes to the con- ASTRONOMY. 35 elusion that the accounts which remain to us are in no one case sufficient to connect the eclipses computed back from modern data with the phenomenon recorded by the historian. In many cases it is not even certain that this phenomenon was an eclipse at all. 2. The nineteen eclipses of the "Almagest" give data which are at the best uncertain. 3. The eclipses of the Arabian astronomers, which are now lor the first time utilized. 4,5,6. The observations ofTycho Brahe,etc.,of Gassendus and Hevelius, are not valuable for this purpose, as they were taken without the aid of telescopes, and are not of sufficiently ancient elate. 7. The observations of De la Hire, De l'Isle, and others, from 1072 to 1750, are now discussed for the first time, and prove to be most valuable material. From 1750 to 1860 or 1865, Hansen's tables represent the observations well. The whole series is represented by omitting the empirical terms of Hansen depending on eight times the mean motion of Venus. The value of the acceleration from observation alone is 8.8", Hansen's adopted value being 12.17". This value 8.8", however, requires to be changed by 0.9" in a century to satisfy observations, and there are several ways in which this may be effected. The rotation of the earth may not be uniform, the analytical theory may not be com- plete, or other and undiscovered bodies may enter in. A term expressing the total correction to Hansen's tables is deduced and provisionally adopted. Its theoretic basis re- quires further investigation. Dr. Haughton has considered these ancient eclipses in a memoir read to the British Asso- ciation. Dr. Weiler has also a series of papers on the theory of the secular acceleration in the Astronomische Ncichrichten, No. 2060 et seq. In 1787 Sir William Herschel announced that he had ob- served three volcanoes in active operation in different parts of the moon, the diameter of the principal crater being about three miles. In May, 1877, Dr, H. J. Klein, of Cologne, while examining the moon, noticed a great black crater on the Mare Vaporum, and a little to the northwest of the well- known crater Hyginus. He describes it as being nearly as large as Hyginus (or about three miles in diameter), as being 3(3 ANNUAL KECORD OF SCIENCE AND INDUSTRY. deep and full of shadow, and as forming a conspicuous object on the dark gray Mare Vapornm. Having frequently ob- served this region during the last twelve years, Dr. Klein felt certain that no such crater existed there at the time of his previous examinations. lie communicated his observa- tions to Dr. Schmidt, of Athens, who assured him that this crater was absent from all his numerous drawings of this part of the lunar surface: neither is it shown by Schroter, Lohrmann, or Madler. Dr. Klein made his discoveries known generally, and they seem to have been partially con- firmed by other observers. The Mare Vapornm, in which the new crater is situated, lies close to the centre of the visible surface of the moon, so that objects in this region are very slightly affected by the lunar librations. It is also a part of the moon which has been most carefully studied. Had this new crater of Dr. Klein's appeared in a less well known re- gion, much more doubt would have been felt as to whether it had previously existed or not. COMETS; METEOR STREAMS. The comets of 1878 have been Comet I., discovered July 7, by Lewis Swift, of Rochester, N. Y. This comet was only observed in America by Dr. C. H. F. Peters, the majority of American observers being in the West on eclipse expeditions. It is probably identical with a comet discovered by P. Ferrari at Rome in July. On Julv 20, Tempel's periodic comet was found by Winnecke, quite away from its ephemeris place. Orbit of Comet IV., 1873.* M. Raoui Gautier, of Leipsic, has discussed all accessible observations of this comet, extend- ing from August 20 to September 20, and, though the period of visibility was not long, the data make it tolerably certain that the orbit is elliptic, the sum of the squares of the re- siduals being reduced from 81.18 on the hypothesis of a parabola to 2.14 on that of an ellipse, while the probable error of an observation is reduced from 6.04" to 1.14". The eccentricity of the ellipse is, however, very large, correspond- ing to a period of revolution which may perhaps range from 3000 to 3G00 years, so that this comet is to be classed among those of very long period. * Astronoi/iisc/ie Nachrichten, No. 21G4. ASTRONOMY. 37 One of the most important papers of the year is by Pro- fessor Newton, of Yale, on the " Origin of Comets." It is impossible to give here an abstract of this paper, which is itself a series of propositions, each in a condensed form, and each closely connected with every other. We can only refer to this as a body of doctrine which will become the Principia of this subject. In the Monthly Notices, R. A. S. (1878, May, p. 869), Pro- fessor A. S. Herschel has a "List of Known Accordances be- tween Comets and Observed Meteor Showers," which will be useful. Seventy-one such are noted. Encke's comet was found on August 3, by Mr. Tebbutt, of "Windsor, jN". S. W., with a 4^-inch telescope. The comet was 2' in diameter, and pretty bright. ZODIACAL LIGHT; METEORITES. The "Results of Ooservations of Shooting-Stars from 1833 to 1875," by the late Dr. Heis, of Minister, has been publish- ed. It comprises Dr. Heis's own observations for forty-three years at the observatory of which he was director. Ac- cording to Nature^ it gives the times of occurrence and the points of first and last appearance of 13,000 meteors, fol- lowed by a partial discussion of the results, and catalogues of radiant points. The zodiacal light continues to be observed by Mr. Henry C. Lewis, of Germantown, Pa. NEW OBSERVATORIES, NEW INSTRUMENTS, ETC. Accounts of European and American observatories are giv- en elsewhere. Anew private observatory has been founded in Providence, R. L, by Mr. George A. Seagrave. The building is of brick, with a wooden dome. The principal instrument is an equa- torial refractor of eight inches aperture, from the workshops of Alvan Clark cttin<- familiar with the instruments, testing their powers, determining er- rors, etc. The transit of Mercury was observed last May, and the results communicated to the U. 8. Naval Observatory. The longitude, as approximately determined at that time, is 10 m 25.7 s E. of Wash- ington. A Driving-clock will soon be attached to the Equatorial, after which it is intended to make measurements of double stars as leisure per- mits. New Haven, Conn. : Observatory of Yale College. In charge of Professor C. S. Lyman ; no regular assistants. Instruments. 1. A 9-inch Equatorial, by Alvan Clark & Soxs, with Dricing-clock, Bijilar Position Micrometer, by Dolloxd; a Multi- ple Ring Micrometer (four concentric rings with widths and spaces equal) ; and a powerful Clark Spectroscope of seven prisms twice traversed by the light. 2. A Meridian Circle, by Ertel & Sons, altered by Youxg, with 5-foot telescope of 3.8 inches aperture, and two 40-inch circles read by six micrometer microscopes. 3. A Sidereal Clock, by Appleton, London, and another by How- ard, Boston. 4. A combined Transit Instrument and Zenith Telescope, of 3 feet focus and 2.G inches aperture. This instrument, the earliest of the kind, was constructed mainly in 1852-53, and is described in the American Journal of Science and Arts, vol. xxx., 2d series, and in the Proceedings of the American Association for the Advancement of Science for 18G0. 5. A portable Clark Refractor, of 5 feet focus and 4f inches aperture. 6. Sextants, and other minor instruments. This observatory is connected with the Sheffield Scientific School, and is used chiefly for purposes of instruction. The only observa- tions published the past year were those of the transit of Mercury. The city time is regulated by the observatory, as well as the chro- nometers coming to this port. Mr. Wm. Beebe and Mr. II. A. Hazen were in charge most of the year, in the absence of the director. Y'alc College has also a 10-foot Befractor, of 5 inches aperture, by Dollond, and a 5-foot Transit Instrument, of 4 inches aperture, by TBOUGHTOH & Si.m.ms. The former is used by students in the Aca- demical Department, and is in charge of Professor Loomis. The latter is not yet mounted. ASTRONOMY. 69 The Winchester Observatory is still infuturo. The ample endow- ment, however, secured to it prospectively by Hon. O. F. Winches- ter, makes its realization only a question of time. A Flint Disk has been purchased, and other steps taken towards the construction of an Equatorial of about 28 inches aperture. New York, N. Y. : Private Observatory of William T. Gregg, Esq. In reply to your card I would say that my observatory was built for the convenience of correcting objectives rather than for star ob- servations ; and yet, if I could do any work in it that you might sug- gest, I would be pleased to do so. I have in it a G^-inch Equatorial (my own make), not furnished with clock-work as yet, but which will be as soon as possible ; and, as I have said, I would gladly undertake any elementary work that you might suggest. Oxford, Miss. : Observatory of the University of Mississippi. Professor R. B. Fulton, Director. The equipment of the Observatory of the University of Mississippi consists of an equatorially mounted Refractor, 4i inches aperture, by Merz, of Munich ; a Portable Transit, 2\ inches aperture, by Pike & Son; an Alt- azimuth, with circles 10 inches diameter and ver- niers reading to 10 s ; a Box Chronometer by Wm. Bond & Son. With the present small equipment, there has not been much work under- taken. The determination of local time, and the observation of the transit of Mercury in May, is all that has been done. The observa- tory has been closed, on account of yellow fever, since July 1. Peconic, Suffolk Co., N. Y. : Private Observatory of Geo. W. Fitz, Esq. Our instrumental equipment is as follows : 1. A 6-inch Telescope, of H. G. Fitz's make, mounted equatorially without circles. It is provided with a Position Micrometer and Eye- pieces of various powers. 2. A 4-inch Telescope, equatorially mounted on tripod stand, with small circles reading to 5' of arc and 4 m of time respectively. It has also a tangent screw for slow motion in R. A. 3. A 32-inch fixed Transit, mounted on a barrel of gravel, capped with a square stone, in a small transit house. It is furnished with a Level and the other means of making the necessary adjustments, also a Setting-circle reading to V. 4. A Dent Chronometer, beating half-seconds. We observed the transit of Mercury on May 6, last, the results of which were communicated to the U. S. Naval Observatory. The fol- TO ANNUAL RECORD OF SCIENCE AND INDUSTRY. lowing arc the times oftlie contacts in "Washington time as obtained by telegraph : 1st contact, estimated 10* 4 m 25 s A.M. 2d " " 10 h 7 m 33 s " 3d " " 5 b 33 m 30 s P.M. 4th ; ' " 5 h 3G m 42 s " These observations are all we have made hitherto ; but next year I hope to make a better showing by transit work, occultations, etc. I have obtained our latitude and longitude roughly by triangula- tion, using Horton's Point light and Southold spire ; the latitudes and longitudes of these places taken from Coast Survey Report for 1851. They are as follows : Lat. 41 2' 15" N., long. 4 h 49 ra 51 s W. of Greenwich, long. 18 m 20 s E. of "Washington. Phelps, N. Y. : Private Observatory of Wm, Robert Brooks, Esq. My apparatus is portable, and the " observatory " is really the yard and garden of my house. I am the only observer, my wife acting occasionally as assistant. Two Telescopes, one a 2-inch achromatic, of 36 inches focal length, the other a Newtonian glass reflector, of 5 inches aperture and 50 inches focal length, both of my own construction, are available. My observations for the past year have been devoted to the planets, moon, and solar spots ; of late, almost daily observations of the sun for spots, and watching for the transit of Vulcan, or other inter-Mer- curial planet. These will continue to be my chief studies for the future. I observed the transit of Mercury last May. My publica- tions have been confined to several notices of interesting phenomena coming under my observation, mainly in the daily and weekly press. Poughkeepsie, N. Y. : Observatory of Yassar College. Professor Maria Mitchell, Director. 1. The personnel of the observatory consists of myself only, al- though aid is obtained from one or more of the students. 3. Subjects of Observation. The sun-spots are photographed on every fine day. Observations were made on Saturn and its satel- lites during fifty evenings in 1877, '78. 4. The above observations will probably be continued in 1879. 5. The only publication was a short article in Sillimaii's Journal on Jupiter. Providence, R. I.: Private Observatory of F. E. Seagrave, Esq. Lkonakd Waldo, Assistant at the Observatory of Harvard College, Director. This private observatory was erected by Mr. Frank E. Scagrave in the rear of his residence, 119 Benefit Street, Providence, R. I. Its ASTRONOMY. 7! position, referred to the neighboring Coast Survey stations, is lati- tude 41 49' 46.4" N., longitude 52 m 34.51 s E. of Washington. The building is a substantial cylindrical tower 18 feet in diameter and built of brick, surmounted by a drum which revolves on gun-metal balls. It was completed, and the instrument mounted, in the spring of 1878. The 'personnel of the observatory at present comprises my pupil, Mr. Frank E. Seagrave, Jun., and myself; the instruments are: 1. An 8-inch Equatorial, by Alyan Clark & Soxs, completely furnished with clock-work, circles, etc., for micrometric measurement ; 2. A number of small Telescopes from 3 to 1^ inches aperture for various uses ; 3. Three Spectroscopes of from ten to one-half prism (of 60 flint) dispersion ; 4. Box Chronometer, Pocket Chronometer, Meteorolog- ical Instruments, and the usual miscellaneous apparatus for use with an Equatorial. During the past year the following subjects have engrossed our attention : 1. The observation of the total solar eclipse from Fort Worth, Texas ; 2. The observations of the satellites of Saturn; 3. The observations of p Cassiopeia^ to investigate its large proper motion; 4. Some desultory measures, when the Equatorial was not needed for the other series of observations, of Burnham's double stars. During the coming year we hope to continue the above series of observations. Our work under the first item will be included in the report of the Fort Worth eclipse party (now in press), and it is probable the work under the second item will be printed within six months. EockesteiyN. Y. : Private Observatory of Professor Lewis Swift. My prospective observatory being not yet completed, and my pres- ent Telescope a 4^-inch achromatic being, as heretofore, mounted as an alt-azimuth, and therefore not well adapted to other work, I have devoted every clear moonless night to comet-seeking, and the charting of such nebulae as had escaped detection during the many years devoted to comet-seeking. I have had the good fortune to discover one new comet, which is, up to this date (Nov. 20), the only new one of the year. I first ran upon it on the morning of July 7, at 2 o'clock civil time, in, by estimation, R. A. 17 h 37 m , Dec. -|-18 . I immediately suspected its cometary character, and, during the half- hour only between then and dawn, my suspicions were verified by the detection of motion. I at once gave the customary notification to the Smithsonian Insti- tution; but, although its discovery was immediately cabled to Eu- rope, it seems not to have been observed there, owing probably to the presence of moonlight ; though, to prove that its taintness was 72 ANNUAL RECORD OF SCIENCE AND INDUSTRY. not excessive, I was able, on the evening of the day of its discovery, to observe it in the presence of a nearly hall-moon. Professor Peters, the Director of the Litchfield Observatory at Clinton, N. Y., and O. W. Landreth, assistant observer at the Dudley Observatory, Albany, N. Y., Mere the only ones, in any part of the world, who were so fortunate as to get a glimpse of it. Professor Peters followed it until August, and his valuable ob- servations enabled Professor Holetschek to compute its elements, which seem to be unlike those of any other known comet. When the moon withdrew, and at the termination of a long peri- od of cloudy weather, when it would have been possible for me to re-find the comet, I was on my way to Denver to observe the eclipse of July 29, at which time I discovered what I consider to be (and which I think astronomers generally, when they are conversant with all the circumstances, will concede to be) two intra-Mercurial plan- ets. This, probably, is not the place to go into details; but if any- thing be said, it seems as if I could hardly say less than what fol- lows : Professor Watson, at Separation, observed 9 Cancri, and, 42' southeast of it, what was undoubtedly an intra-Mercurial planet. I, observing in the same region, saw two stars, one of which, I took for granted, as did everybody, was 9 Cancri, and the other the same planet Watson had discovered five minutes previously. But upon comparison of observations, and after the elimination of all probable errors, I found so much discordance as to justify the prediction that I had not seen 9 Cancri at all, but, rather, had discovered two plan- ets neither of which was seen by Watson, nor was his planet seen by me. It may be proper to state that Professor Watson discovered still another planet, farther from the sun and near to . On the 23d I shall start for Cambridgcport, to order, from Alvan Glare & Sons, my new Telescope. It will probably be of 9 inches aperture, and is to be provided with all the modern improvements. The observatory will probably be ready for the reception of the Telescope when finished. For the coming year I design to continue comet-seeking as here- tofore; but, as I shall have enlarged facilities and improved means for micrometric measurements, I also purpose to determine the posi- tion of nebula?, and to measure close double stars. I shall make de- termined eftbrt with high powers to detect some of the intra-Mer- curial planets while in transit, and perhaps near their greatest elon- gation. San Francisco, Cal. : Office of u The James Lick Trust." In response to your annual circular, recently received, I have little to say in addition to former advice. The litigation is still progressing. In January last the trustees received a favorable decree in the Nineteenth District Court. The ASTRONOMY. 73 cause has been appealed to the Supreme Court, and is on calendar for the next ensuing term thereof. The trustees hope soon to receive judicial confirmation of their position beyond further appeal, and are uuanimous in their desire to proceed with the work of erecting the " Lick Astronomical Observ- atory " as speedily as possible. Sonth Bethlehem, Pa 6 ? Sayre Observatory of Lehigh University. Professor C. L. Doolittle, Director. Your circular inquiring as to the status, etc., of the Sayre Observa- tory came to hand in due time. In reply to the same I will say that no change in the personnel or management of the observatory has been introduced during the year. The object of the observatory is mainly that of instruction. Any other work which is attempted must be of such a character as not to interfere with this. I, however, try to do something in the way of scientific work, with such assistance as I am able to get from my pupils. The instruments are as follows : An Equatorial Telescope of 6 inches aperture, by Clark & Sons ; a Sidereal Clock, by Bond ; a Zenith Telescope, by Blunt ; and a Port- able Transit Instrument, by Stackpole. Besides the time given to the work of instruction, I have during the last year completed the determination of the latitude from a se- ries of over 400 pairs of stars observed with the Zenith Telescope. The declinations of the stars used were reduced very elaborately from all the catalogues since that of Bradley, giving a series of mean declinations and proper motions which I hope will not be wholly without value for other purposes. Besides this, a series of measure- ments of Jupitefs satellites has been made, together with observa- tions of eclipses and occultations of the same, which will soon be sent for publication to some scientific journal. The transit of Mer- cury was successfully observed, the time of all four contacts being noted, and notes made of the physical appearances. It is my intention to continue the observations of Jupiter at the next opposition, and to give such attention to special phenomena as opportunity may offer during the coming year. All of our students in the departments of Civil and Mining Engineering have a pretty full course in practical astronomy, which includes observatory work ; besides which I have several advanced pupils who are making as- tronomy a special study. St. Louis, Mo. : Observatory of Washington University. Professor J. K. Kees, Director. In answer to your letter of inquiry, I beg to say that our observatory was built last June, and has been used mainlv for class instruction. D 74 ANNUAL KECOKD OF SCIENCE AND INDUSTRY. 1st. The personnel consists of myself and a volunteer assistant, Mr. E. A. Engler, a graduate of the university. 2d. Instruments. A Refractor, by Fitz, cquatorially mounted, and of 17 centimeters (6.G9 inches) clear aperture. This instrument is supplied with a Driving-clock and a Filar Position Micrometer. A Refractor of 7.5 centimeters (2.95 inches) clear aperture, univer- sally mounted. This is about to be better adapted to transit-work. To this may be attached a fine diagonal Micrometer Eye-piece for de- termining latitude bv Talcott's method. A Sextant, by Geo. W. Blunt. 3d. Observations. No regular observations are made except for time, which is supplied to the city by means of a Central Regulator, communicating by electricity with thirty dials situated at different points. This summer I was a member of the party stationed at Fort Worth to observe the eclipse of July 29. I have a Rutherfurd Diffraction -plate of 17,280 lines to 2.5 cen- timeters, which I expect to have mounted so as to do some work in solar physics. Tarrytowii, N. Y. : Private Observatory of C. H. Rockwell, Esq. In reply to your note of inquiry, I would say that my astronomical outfit is so meagre, and the work done so unimportant, as scarcely to merit a public notice. In company with Mr. Ward Carpenter, of this village, I made ob- servations on the transit of Mercury on 6th May last, of which I sent an account to the Naval Observatory, Washington, by request of Ad- miral John Rodgers. The instruments used were a Telescope of 3J inches clear aperture, a Mean-time Chronometer, No. 459, by Par- kinson & Frodsiiam ; and an Engineer's Transit, with diagonal Eye- piece, for time observations of stars. I went to Central City, Col., as a member of the party under the charge of Professor Edward S. Holden, of the Naval Observatory, to note the solar eclipse of July last. My interest in astronomical matters is largely on the side of math- ematics, and the calculations which I make are only those of an am- ateur. Troy, N. Y. : Proudfit Observatory. Professor D. Greene, Director. This observatory is the gift of Ebenezer Proudfit, Esq., of Troy, to the Rensselaer Polytechnic Institute, and is just completed. It is designed mainly to furnish facilities for the practical instruction of students in astronomy. The building is of brick, and consists of a central part thirty feet square and two stories in height, with north, south, and east wings. The Equatorial room, in the second story, is ASTRONOMY. 75 circular, and is covered with a revolving dome twenty-nine feet in diameter, which weighs but 4000 pounds, and can therefore be easily revolved without machinery. The piers for the meridian instruments are in the east wing. The central part of the roof of this wing is flat and is surrounded by an iron railing ; it is directly accessible from the Equatorial room, and forms a convenient place for the use of por- table instruments. The following are the only instruments yet in the possession of the observatory : Transit Instrument, by Kubel, of Washington, of 2^ inches aper- ture and 31 inches focal length. It is so made as to admit of ready reversal, and is provided with delicate Level and Micrometer, to adapt it for use as a Zenith Telescope. Another Transit, of 2 inches aperture and 30 inches focal length, is mounted in the prime vertical. Telescope, by Fitz, of 3 inches aperture, mounted on an equatorial stand. For furnishing the time, there are two mean Solar Clocks and a Si- dereal Chronometer. Washington, D. C. : U. S. Naval Observatory. Bear-Admiral John Rodgers, U.S.N. , Superintendent. The report of the Secretary of the Navy for 1878 contains that of the Superintendent of the Naval Observatory, which gives an account of the work of the past year. The 26-inch Equatorial continues to be used in the observations of the faint satellites. The Transit Circle, besides its regular work of observations of the sun, moon, and major planets, has made a very large number of observations of asteroids, and is also engaged in the formation of a catalogue of the B. A. C. stars between 120 0' and 131 10' of N.P.D. The number of observations made with the Transit Circle during the year is 3450. The sun was observed sixty-one times, the moon sixty times, and there were made 110 observations of the major planets and 149 of the minor planets. The Transit - of -Venus reductions are almost ready for publica- tion. The work of reducing the observations for the chronometrical lon- gitudes of five southern stations is now completed. From 23 to 35 Chronometers were used, and the corrections to each one have been computed for every day from August 6, 1874, to January 30, 1875. The principal work of this observatory is described under its ap- propriate heads as Saturn, Mars, Solar Eclipses, etc. 76 ANNUAL RECORD OF SCIENCE AND INDUSTRY. Wilier* Point, N. Y.: Field Observatory of Engineer Battalion. Brig.-Gen. Henry L. Abbot, U.S.A., Director. In reply to your request for information about our astronomical work, I would say that this post constitutes the school of applica- tion, at which officers of engineers receive facilities for becoming familiar with the practical duties of the coitjs. In astronomy, we have a good field observatory, provided with all the instruments used in first-class boundary work, including Transits, Zenith Telescopes, Astronomical Telescopes, Sextants, Break-circuit Chro- nometers, and Field Chronographs. The work during the past season has consisted in the usual obser- vations for latitude, longitude, and time. Advantage was also taken of the transit of Mercury. A 5-inch Equatorial, used on the transit of Venus, was borrowed from the Naval Observatory, and a good set of observations were made. A detached report was sent to Admi- ral Rodgers, which will appear in his general report upon the sub- ject. For several years past a regular nightly series of records of displays of the Aurora Borealis has been systematically kept, which I propose to publish at some future time. They show clearly the well-known law connecting them with solar spots. Yellow Springs, 0. : Observatory of Antioch College. Professor Chas. H. Chandler, Director. Your circular asking for an account of our observatory is received. I am very sorry that the fact is that we have none. We have a very good Telescope, by Alvan Clark & Sons, of 12^ centimeters (4.94 inches) aperture, mounted equatorially upon a portable tripod, as we have no building for its permanent location. This, with a Negus Chronometer and a small Pistor & Martins Reflecting Circle, consti- tutes all the instruments that are in any way available for astro- nomical purposes. These instruments are used only for instruction in the regular col- lege classes, and the press of instruction devolving upon me is such as to prevent other work on my part. REPORTS OF EUROPEAN OBSERVATORIES. THE OBSERVATORIES OF ITALY. Professor Rayet, of Marseilles, has recently been deputed by the Minister of Public Instruction of France to visit the various observ- atories of Italy, and to report upon them. His report is published in the Archives des Missions Scientiflques, 3 me seric, tome iii., p. 529. ASTRONOMY. 77 and is much abridged in what follows. For details the original re- port must be consulted, or the excellent resumes in Andre and Rayet's " Astronomie Pratique," vol. v. " In the course of my journey in Italy, I visited successively the ob- servatories of Palermo, Naples, Rome (that of the Roman College as well as that of the Capitol), Florence, Bologna, Modena, Padua, Mil- an, and Turin, remaining some time at each. It is the intention of the government to maintain all of them, each one being devoted, however, to a different branch, so as to fulfil the various needs of astronomical science, now become so complex. " Of these observatories, only that of Naples has a considerable num- ber of assistants, and in no one is the work done under rigid regu- lations ; each astronomer devotes himself, according to his predilec- tions, to a special subject ; emulation and the desire to make a name in science produce a continuity of effort, the result of which has in the last few years been manifest in various brilliant discoveries. To show this, it will be sufficient to describe briefly the situation of each observatory, and the work upon which it is at present engaged." The Observatory of Palermo. M. Cacciatore, Director; M. Tacchini, Astronomer. " This observatory contains two important instruments : a Meridi- an Circle, by Pistob, & Martins, and an Equatorial, by Merz, which was mounted in 1865. The Meridian Circle is daily employed in observations of the sun and the principal stars. The principal work, however, of the Observatory of Palermo, which is specially under- taken by M. Tacchini, is the daily study of the solar protuberances. " In Italy this research is most vigorously prosecuted, and, in order to avoid the interruptions in a series of such observations which cloudy days may occasion, the observatories of Palermo, Rome, and Padua prosecute these observations in common. "Among the interesting historical instruments of the observatorv is the Altitude and Azimuth Circle, made by Ramsdkn in 1788-89, which served Piazzi in the preparation of his great catalogue of stars." The Observatory of Naples. M. De Gasparis, Director ; MM. Fergola, Brioschi, and Nobile, Astronomers. " The Observatory of Naples is the most important of those of Italy, in its equipment and its personal establishment. It was founded in 1812 by Murat, and it is built in agreement with modern ideas. In the west Meridian room are a Transit Instrument, by Reichexbach, and a Meridian Circle, by the same artist. These are still in use. The east Meridian room contains a Meridian Circle by Repsold, which has just been mounted, and which is one of the best of the instru- 78 ANNUAL RECORD OF SCIENCE AND INDUSTRY. merits of this class made by this celebrated artist. It is with this instrument that M. Fekgola is observing the zone of stars which the Observatory of Naples has undertaken for the German Astronomical Society. Besides the three Meridian instruments, the Observatory of Naples has in active use two Equator ials, and is soon to obtain a third ot larger dimensions. The first of these instruments was constructed in 1811 by Reichenbacii & Utsciineider, and has 3.27 inches aperture. It is with this small instrument that M. de Gas- paris discovered nine asteroids, Hygeia, Parthenope, Egeria, Eunomia, Psyche, Massilia, Themis, Ausonia, and Beatrix. The second Equato- rial was made by Merz, of Munich, and has an aperture of 5.28 inches. M. Nobile employs it in the measurement of the double stars of Struve's catalogue. " Observatory of the Roman College. Padre Ferrari, Director. " The observatory formerly under the direction of Padre Secchi is built upon the top of the cupola of the Church of St. Ignatius ; but in so solid a way that the stability of the instruments, during the night at least, is quite satisfactory. The principal instrument of the ob- servatory is an Equatorial of 7.5 inches aperture, which is one of the chefs-d'eeuvre of Merz. There is still another Equatorial, by Cauchoix, of 5 inches aperture, which is used for the daily observations of so- lar spots, and also a Transit Instrument, by Ertel, for time deter- minations. The situation of the observatory, in the centre of the city, has forced its illustrious director to devote his efforts to the study of physical astronomy, which, in his opinion, is too much neg- lected in government observatories. " To recite the magnificent works executed in this branch of astron- omy by Padre Secchi would require too much space, but I may men- tion a new experimental method used by Padre Secchi in his stud- ies of the solar protuberances. For more than a year he has employed, in place of the prisms of his spectroscope, a diffraction-grating ruled upon a speculum metal by Mr. Rutherfurd, of New York. This grating lias 4000 lines to the English inch, and gives a spectrum whose definition leaves nothing to be desired. For the studv of the solar prominences such a grating appears to me infinitely superior to any combination of prisms." Observatory of the Capitol. M. Respighi, Director ; M. Scarpellini, Assistant. " The second observatory in Rome, that of the Capitol, is under the patronage of the Academia dei Nuovi Lincei. M. Respighi is now occupied in observations of solar protuberances and in meridian ob- servations, serving as basis for a catalogue of stars. For the first ASTRONOMY. ^9 purpose an Equatorial, by Merz, of 4^ inches aperture, and a direct- vision Spectroscope, with five prisms, are employed. " A beautiful Meridian Circle, by Ertel, serves M. Respigiii for his observations of fixed stars of the first six magnitudes, which are to be employed by the Italian staff-officers in their geodesic operations. This observatory possesses also a Reflex Zenith-tube, made by Ertel from designs by M. Respighi himself. The basin of quicksilver, by means of -which the reflected stars are observed, is 21 meters (68.90 feet) below the objective, which thus masks but a small portion of the sky. When the telescope is directed towards the nadir, stars very close to the zenith may be observed by the declination-wires during their transit ; at the same time, and without touching the in- strument, the nadir may also be observed, so that the zenith-distance of each star depends upon the micrometer screw alone, and is de- termined with the great accuracy which this kind of observation allows." Observatory of Florence. M. William Tempel, Assistant. " The old observatory of Florence, formerly presided over by Do- nati, has been dismantled, and a new and magnificent structure is nearly built at Arcetri, near the house formerly inhabited by Galileo. The old observatory is now used for a meteorological station. "The new observatory possesses, 1, a small Equatorial suitable for a comet-seeker; and, 2, a large Equatorial, by Amici, of 11 inches aperture, of excellent quality. Besides this, a small Meridian In- strument is mounted in the Meridian room. This room will subse- quently contain a Meridian Circle of 7 inches aperture, and a Tran- sit Instrument somewhat smaller. It is proposed to have for this ob- servatory a staff composed of a director and five assistants." Observatory of Bologna. M. Palagi, Director. "The Observatory of the University of Bologna is one of the most ancient in Italy, and is placed on the top of a high tower, which un- fits it for precise observations. It possesses a Meridian Circle, by Er- tel, mounted in 1851, but now little used, and also a Dollond Equa- torial, of 3 inches aperture. Its collection of historical instruments is of high interest." o Observatory of Modena. M. Ragona, Director. "The Ducal Observatory was founded in 1819 by Bianciii, and was provided with the best instruments of that time ; but now it 80 ANNUAL RECORD OF SCIENCE AND INDUSTRY. -will probably become the central meteorological station of the sur- rounding states. Its Meridian Circle is of 4 inches aperture, "with 3-foot circles. Its Amici Equatorial has 2-J- inches aperture only, and is thus too small for most astronomical purposes. Its collection of meteorological and magnetic apparatus is, on the contrary, very com- plete and noteworthy." Observatory of Padua. M. Santini,* Director; M. Lorenzoni, Astronomer. " This observatory dates from 1774. It is well situated for obser- vations of precision, as the numerous catalogues of stars published by its celebrated director testify sufficiently. The principal instru- ments of the observatory are a Meridian Circle and an Equatorial, both by Starke. There is also a Spectroscope by Hoffman. The two latter instruments are used by Lorenzoni for daily observations of the solar protuberances. The Meridian Circle is employed in ob- servations of the sun, planets, and the principal stars." Observatory of Milan. M. Schiaparelli, Director ; M. Celoria, Astronomer. " The Milan Observatory is one of the most ancient of Italy, its foundation in the Brera Palace having been established in 1700. Among its directors have been the celebrated astronomers Boscovicn, Oriani, Cesaris, and Carlini. It contains two halls, one for the Equatorial and one for the Meridian Circle. The former, by Merz, was mounted in February, 1875. It is to be devoted to a re-observa- tion of Struve's double stars. The Meridian Circle is by Starke." Observatory of Turin. M. Dorxa, Director; TNI. Charrier, Assistant. "The present observatory of Turin was constructed in 1820, and until 1864 it was under the direction of the illustrious Plana; since that time it has been part of the university, and is under the charge of the Professor of Astronomy. Its instruments are: 1. A Meridian Circle, by Reichenbacii. This excellent instrument is used for obser- vations of the sun and stars for the determination of the time, which is given to the city by means of a time-ball. 2. A Comet-seeker, mounted in a small dome. 3. A Bepcatiiui-circle, by Ertel, used for purposes of instruction. 4. An Equatorial, 4.01 inches aperture, which will be used by Dr. Charrier for spectroscopic observations of the solar protuberances. A larger Equatorial is soon to replace this." Died July, 1ST7. ASTRONOMY. gl OBSERVATORIES OF PORTUGAL. From an official document of the Portuguese government we extract the following, which will contain something new to most readers : " Portugal possesses three astronomical establishments : The Lisbon Royal Observatory, the Astronomical Observatory of Coimbra Uni- versity, and that of the Lisbon Polytechnic School (in construction). "In 1874 the ancient Marine Astronomical Observatory in Lisbon was abolished and annexed to the Naval School, for the practical study of astronomy and navigation in the course of the same school. It has under its charge the regulation of the chronometers and de- termination of error of the instruments destined for the men-of-war. " The principal instruments that this observatory possessed were : 1 Repsold Meridian Circle, with a focal distance of 1.36 meter, and the objective of 0.10 meter of diameter; 1 Transit Instrument; 1 Parallactic Refractor, with a focal distance of 2.61 meters and object- ive of 0.155 meter; and 1 Repsold Universal. "The Lisbon Royal Astronomical Observatory is indebted to the love of science and liberality of the king, Don Pe- dro V., and to the initiative of Dr. Filippe Folque. The plan of the observatory is similar to the one of Pulkova. Height of the place, 93 meters. " The collection of instruments of the observatory consists of 1 large Equatorial of a focal distance of 7 meters and 0.38 meter of objective aperture ; 1 Prime Vertical Transit Instrument, Struve's system, with 2.31 meters of focal distance and 0.16 meter of aper- ture ; 1 Meridian Circle, with 0.15 meter of aperture and 2 meters of focal distance; 1 Transit Instrument of the system of Oom, with 0.07 meter of aperture and 0.78 meter of focal distance ; 1 Parallac- tic Refractor of 1.95 meter focal distance and 0.117 of aperture; an Explorator of 0.64 meter of focal distance and 0.077 meter of aper- ture; a Normal Pendulum of Krille, regulator of electro-chrono- metric apparatuses; several Chronometers and Pendulums; 1 Chron- ograph; Electric Apparatuses; 1 Zigometer; Collimators, Barometers, Thermometers, and Telegraphic Apparatus. "The Coimbra Observatory, whose establishment is indebted to the Marquis of Pombal, is built alongside of the university building, and is destined principally to the practical teaching of astronomy in the faculty of mathematics. " The principal instruments that it possesses are : Equatorial. Me- ridian Circle, Prime Vertical Transit Instrument, and sidereal pendu- lum of Berthoud. " The technical personnel consists of a director, two astronomers, and two calculators." D 2 82 ANNUAL RECORD OF SCIENCE AND INDUSTRY. OBSERVATORIES OF ENGLAND AND ENGLISH COLONIES. The Monthly Notices of the R. A. S. for February, 1878, contains the reports of the proceedings of observatories, "which may be summarized as follows : Greenwich Observatory. The Meridian and Alt-azimuth instruments are employed as in former years. The Equatorial has been used for drawings of Mars, on the spec- troscopy of the sun, moon, Mars, and fixed stars, and of the " rain- band" in the solar spectrum : 109 photographs of the sun have been taken. The computations for the nine-year catalogue of 2363 stars are finished. Radcliife Observatory, Oxford. The usual routine work has been done, and solar spots observed. The Heliometer has been employed on Mars and Saturn; twenty-five measures of Saturn s diameter have been made. The catalogue of stars is advancing. University Observatory, Oxford. The Savilian Observatory, Oxford, has published Part I. of its as- tronomical observations. It describes the instruments of the obser- vatory, and gives a series of observations of satellites of Saturn one of Mimas (?), ten of Enceladus, none of Hyperion, and from forty- five to ninety-seven of the brighter satellites. Part II. contains four hundred observations of 118 double stars. Part III. is de- voted to the comets of 1877, which were well observed. Part IV. contains new orbits of three of the older binaries. Twelve hun- dred photographs of the moon have been taken, and are to be measured to determine the anfount of libration. The geographical co-ordinates of the observatory are given to 0.001", or about one inch on the earth's surface. These are quoted from Ordnance-Survey data. University Observatory, Cambridge. The zone observations are continued. Dunsink Observatory. The red stars of Bebjellerup'a catalogue have been nearly all ob- served, and the Equatorial has been employed in measures to deter- mine the parallax of stars. Edinburgh, Liverpool, and Glasgow Observatories. The usual routine work is continued. The Edinburgh Observatory has issued its fourteenth volume, un- ASTRONOMY. 83 der the direction of Piazzi Smyth. Its main space is devoted to the formation of a kt star ephemeris" from 1830 to 1890, which is to be compared with standard observations. Much of this is blank. Portions of the work are devoted to rain-band spectroscopy, to a discussion of the valuable series of earth-temperatures, etc. Kew Observatory. Besides reductions of solar photograms, the spots are observed with the eye. Temple Observatory, Rugby. The new observatory is completed, and measures of double stars continued. Dr. Huggins's Observatory. Photographs of the spectra of Sirius, Mars, Venus, Jupiter, Saturn, and the moon have been made. Cape of Good Hope Observatory. Three thousand stars between 125 and 135 1ST. P. D. of Lacaille's list have been observed. Mars has been observed thirty-eight times on the meridian for parallax. The time-service has been extended. Melbourne Observatory. The regular work is continued, including daily photographs of the sun. The zone observations between 150 and 160 N. P. D. are near- ly complete. They comprise 48,000 stars, from first to tenth magni- tude. OBSERVATORIES OF THE CONTINENT OF EUROPE. In the Vierteljahrsschrift der Astronornischen Gesellschaft, 1878, there have been collected short reports on the activity of various Eu- ropean observatories, of which reports we give an abstract here. The observatories chosen are usually such as do not regularly pub- lish an annual (or other) volume ; so that these abstracts, taken in connection with the published volumes, furnish a record of trans- atlantic work similar to that which we have collected for American observatories. Observatory of the Academy of Sciences, Berlin. Director of the Observatory, Professor W. Foerster ; Director of the Computing Bureau, Dr. Tietjex. The principal instruments are : a 7-inch Meridian Circle (Pistor & Martin's), under the immediate charge of Dr. Becker; and a 9.G-. 84 ANNUAL RECORD OF SCIENCE AND INDUSTRY. inch Equatorial (Mebz), under charge of Dr. Knorre. The smaller Meridian instruments are under Dr. Tietjen's care. The principal work of the Meridian Circle was the continued ob- servation of the 521 fundamental stars of the V.Y. S. Catalogue. This work was interrupted in 187(5 by the operations for deter- mining the longitudes of Berlin, Vienna, and Odessa from Green- wich. One thousand three hundred and thirty transits and 1328 declinations were observed in 1877. Various other stars have been added to the observing list, among others 360 stars of Tobias Meyer's catalogue, stars for Mr. Gill's Mars observations, etc. Publications have been made of the work of Dr. Schmidt on the division errors of the small Meridian Circle, and of Dr. Midler on the Micrometer screw of the Equatorial. The time-service has been carried on as usual. Clocks are con- trolled at the Time-ball Stations of Neufahrwasser, Swinemunde, Bremerhaven, and Cuxhaven, as well as six different public squares in Berlin. The principal work of the Computing Bureau has been, as before, the computation of the Berliner Jahrbuch. Twenty minor-planet cir- culars have been issued. Of the thirty-six planets whose new ele- ments are given in these, twenty-seven were computed in the Bureau. Of the sixty-four ephemerides, forty-seven were computed in Berlin. University Observatory, Bonn. Professor E. Schoenfeld, Director. The Meridian Circle is engaged on the zone observations (zone -f40 to -f-50 c ). Dr. Hugo Seeliger observes at the Telescope ; Dr. Deichmiiller at the Microscopes. Five hundred and seventy-four partial zones were observed up to December 31, 1877, and about four hundred and eighty reduced. Comets , &, c, c, and/, 1877, were observed. The Durchmusterung has been carried on, and 70,517 star-positions determined. For comparison, the catalogues of Lalandc, Rumker, Piazzi, Schjel- lerup, Bessel's and Argelander's zones, and the Anonymse of Yar- nalFs Catalogue, have been completely reduced to 1855. For the cluster M. 23 (h. 1990) G. C. 434G, a special Durclimuxtcrung has been made. Over 145,000 star-positions have been fixed during 1870-77. The variable stars Mira and T Monocerotis were observed. Royal Observatory, Brussels. F. Quetelet, Director. A new Equatorial, by Merz, of 0.088 (=14.96 inches, English) aperture, has been ordered, and will be mounted by Cooke. A Meridian Circle, similar to the Strasburg Circle, has been ordered from Refsold. ASTRONOMY. 85 Another Equatorial, 0M5 m (=5.91 inches) aperture, is employed for spectroscopic work. Drawings of Mars were made with it by M. L. Niesten. The new instruments, when installed, will be devoted to three prin- cipal objects : first, to double-star observations of binaries and proper- motion stars ; second, to observations of Jupiter s satellites in transit ; third, to spectroscopic observations, particularly of binaries. The sun is now observed spectroscopically by M. Fievez. Diisseldorf Observatory. Dr. Robert Luther, Director. In 1877 thirty-seven Ring-micrometer observations of fourteen plan- ets were made. Since 1847 there have been made 856 observations of 103 planets. Private Observatory of Dr. Eppsteiu, Frankfort -on -the -Main. The principal instrument is a Newtonian Reflector of 6.3 inches aperture, made by Browning, costing 26. The minimum xisibile Is an 11.12 magnitude star. The work undertaken with the instrument is a continuation of HerscheVs sweeps. The field of view of the sweeping eye-piece is 30', and two hundred fields have been swept and 6700 stars counted (1877 September, October, and November). (xotha Observatory. Dr. A. Kruger, Director. During the necessary repairs of the Meridian Circle (0.075 m aperture, 1.160 m focus), the Helsingfors University has lent its Transit Instru- ment to Dr. Kruger, and this has been used for zone observations (zone +55 to +65). Private Observatory of Herr Yon Konkoly, O'Gyalla, near Komorn. This observatory has three domes, a Meridian room, and a chem- ical laboratory. The instruments are : a Browning Reflector, 10^ inches aperture, 7 feet focus; a Merz Refractor, 6 inches aperture, 6 feet focus; a small Telescope, 3 inches aperture, for sun-spot observations; a Starke Me- ridian Circle, about 3 inches aperture, circles reading to 1" ; two Comet- seel'ei's and minor instruments, and several Spectroscopes ; a Zollner's Pliotometer. The work of 1876-77 has been the formation of a catalogue of one hundred and sixty stars (l rn -6 m ) whose spectra have been observed. Dr. Schrader is assistant, and has conducted a regular series of sun- spot observations. 86 ANNUAL KECORD OF SCIENCE AND INDUSTRY. Hamburg Observatory. Dr. Georg Rumker, Director. The zone observations (zone 80-81 N. P. D.) were continued on forty-five nights. Mars was observed fourteen nights. Observations of nebula?, star-spectra, comets, etc., were made with the Equatorial. The Time-ball Stations of Cuxhaven, Bremerhaven, etc., are pro- vided with time-signals, and the Chronometers of the Priifungs-Insti- tut are compared. Dr. Georg Koch is assistant. University Observatory, Leipsic. Professor C. Bruhns, Director. Herr "Weinek observes with the Meridian Circle. Mars was ob- served on 42 nights, and major and minor planets are regularly ob- served. Dr. Peter, with the Equatorial, has observed on 129 nights, making 176 observations of 35 asteroids, 84 observations of 6 com- ets, etc. Herr Leppig has observed sun-spots on 195 days with the small Equatorial. Herr Harzer has drawn a number of nebula? with a 4|-foot Refractor, and with the Comet-seeker. Herr Harzer has investigated the orbit of Brorsems comet from 1842 to 1846. The first volume of "Leipsic Observations," contain- ing Observations of Nebula? and Double Stars, is printing. The Transit-of- Venus observations are computed at this observa- tory for the German Commission. Private Observatory of Dr. Hugo Gericke, Leipsic. The instrument is a Steinheil Refractor, of 4 inches aperture, and 154 observations of 38 asteroids have been made. University Observatory, Lund. Professor A. Moller, Director. Dr. Lindstet, assistant, has investigated the division errors of the Meridian Circle. Mars was observed on ten nights. Double stars and comets have been observed with the Equatorial. University Observatory, Milan. Professor M. Schiaparelli, Director. Eight hundred and forty measures of double stars have been made with the 8A-inch Equatorial (Mekz). 2 2165, =IIercidis 281 B, was found to be triple. Comets were also observed, and the surface of Mars studied, and a map made. ASTRONOMY. 87 Professor Celoria is computing the longitudes of Monaco, Padua, Vienna, Milan, Naples, and Genoa. The time is furnished to the city of Milan. University Observatory, Mannheim. Dr. W. Valentiner, Director. The cluster G. C. 4410 has been observed assiduously, so that to determine the positions of its 40 stars about 2000 differences in right ascension and about 1000 differences of declination have been made. Two other clusters, G. C. 1166 and G. C. 1454, are observed also, and will probably be completed during 1878. The reduction of the Meridian observations of Barry is so far complete that the printing has already begun in the Jaliresbericlite of the Maniiheimer Verein far Naturl'unde. Nine hundred and thirty-two stars were observed by Barry (about 1805) 2573 times, or an average of 2.8 times per star. The probable error of a right ascension of such an average star is 0.089 s . The library of the observatory contains 1400 titles. University Observatory, Moscow. Dr. Th. Bredichin, Director. In brief, the work of this observatory has been Meridian-circle ob- servations of Mars for parallax, and of various stars ; micrometric observations of the cluster in Perseus ; comet observations ; spectrum of comet 1877, II.; spectroscopic observations of the sun; and pho- tographic observations of the sun and of groups of stars. Vol. IV. of the Moscow Observatory, 1878, has arrived in this country. It is in quarto form, and in two parts. Part I. contains : 1. Meridian-circle observations of stars of a selected list. 2. A second memoir on the anomalous forms of comets' tails, by Pro- fessor Bredichin. This deals with comet 1861, II. 3. Meridian observations of Mars in opposition and comparison stars, by M. Gromadski. These observations extend from July 18 to SejDtem- ber 24. The probable error (AS) of a single observation is 0.58". Each observation of this series combined with one of the same weight in the southern hemisphere w r ould give the solar parallax wuth a probable error 0.19", and hence from twenty such corresponding observations we may expect a value of this doubtful by 0.04". 4. This section is devoted to Meridian observations of a sjDecial list of stars. 5. Spectrum of comet 1877, b. Dr. Bredichin finds this to be : A, 556.4 1.7 ; B, 515.4 0.7 ; C, 469.7 2.2. For Coggia's comet these numbers are : A, 563.0 ; B, 516.0 ; C, 471.1. For the spectrum of "lenzine" they are: A, 563.2; B, 516.4; C, 471.2. Part II. con- tains: 1. Observations of Mars and comparison stars with the Equa- torial. 2. Measures of stars in the cluster in Perseus. 3. Photomet- 88 ANNUAL RECORD OF SCIENCE AND INDUSTRY. ric observations with a Zollner's Photometer; observations of com- ets, of bauds on Jupiter, of a lunar eclipse, etc., and some j)hoto- hcliographic observations. Astrophysikalisches Institut, Potsdam. The buildings are well under way, and some of them are now oc- cupied. Besides the 5-inch Stein heil Refractor, one by Grubb, of 8 inches aperture, has been in use. The principal instrument of the institute, a Schroeder Refractor, of 11.7 inches aperture, is now fin- ished, except the mounting. Dr. Spoerer observed the sun on 229 days in 1877, and on 103 days it was free from spots. The protuberances were also observed. Dr. Vogel has investigated the spectrum of Nova Cygni, and, togeth- er with Dr. Miiller, has made photometric measures in the solar spec- trum. Mars and Jupiter have been studied by Dr. Lohse, who has also examined the structure of solar spots. Dr. Miiller has begun a series of photometric observations on the major planets. University Observatory, Stockholm. Dr. Hugo Gylden, Director. A 7-inch Refractor (Repsold) has been mounted, as well as a Port- able Transit. The principal work of the observatory has been in computation of tables (now published) for general perturbations in comet orbits. University Observatory, Strasburg. Professor A. Winnecke, Director. The Meridian Circle is not yet mounted, and so could not be used on Mars observations as was hoped. Physical observations of Mars were secured on 19 days. With the small Refreictor (6-inch) on 48 nights 124 nebulae were observed in connection with neighboring stars. Observations of six comets, of Nora Cygni, of double and variable stars, have been made with the Equatorial. The Transit Instrument has been employed by Dr. Schur, who has also observed 38 diame- ters of Mars, the diameter of the moon (during the total eclipses of February 27 and August 23), and a few double stars with the Jleli- ometer. This instrument will next be employed in measures of the solar diameters ; and this series it is intended to continue for a pe- riod of eleven years. Dr. Hartwig has already made measures of the polar diameter on G4 days, of the equatorial on 65 days, without detecting the slightest difference. The diameter of Mars has been measured 30 or more times, and thai of Venus on 21 days. ASTRONOMY. 89 University Observatory, Warsaw. Dr. I. Wostokoff, Director. The instruments of this observatory are : Vertical Circle, 3 feet di- ameter ; Transit, 4 inches aperture ; and a 6-inch Equatorial. Dr. Kowalczyk observed with the Meridian Circle stars of the zone 1 50' to 7 10', on the plan of the German Astronomical Society. Fifteen hundred observations have been made. Three determinations of the latitude have been made at this observatory : 1830-43, Meridian Circle, 52 13' 5.6"; 1846, Universal Instrument, 52 13' 5.7"; 1877, Vertical Circle, 52 13' 4.6". Imperial Observatory, Vienna. Dr. Palisa, with the 6-inch Fraunhofer, has observed asteroids and comets. Dr. Weiss has used the same instrument in observing suspected variable stars discovered by him. One of these stars is LI. 28607, which varies from 7.0 to 8.8 magnitude in a period of four months. This star has proper motions of 0.08 s and 0.35". The neigh- boring star LI. 28590 apparently has a proper motion of 0.2''. Another adjacent star, LI. 28590 (double), is slightly variable. Dr. Holetschek is observing, with the Meridian Circle, the funda- mental stars of the Vienna zones, 4-15 and +18. The new observatory buildings will probably be completed in 1878. The crown-glass of Grubb's 27-inch Refractor is not fin- ished. The Clark 12-inch is not yet mounted. University Observatory, Zurich. Dr. It. Wolf, Director. Sun-spots have been daily observed ; in 1877 on 307 days. Draw- ings of Mars, Venus, Jupiter, Saturn, the moon, a few nebulae, etc., have been made by Dr. Wolf. ADDENDUM. The report of the Dudley Observatory, which should have been inserted among those of other American observatories, has not been forwarded to the compiler, although, had time allowed, it would have been prepared by the Director, and inserted here. From data kindly furnished by the Director, the following abstract is given of one important paper; and it may be further mentioned that actual work has commenced on the zone undertaken by this observatory. In a paper on the Transit of Mercury, read before the Albany In- stitute, Professor Lewis Boss, the Director of the Dudley Observatory, 90 ANNUAL 11KCORD OF SCIENCE AND INDUSTRY. has discussed a large number of observations of contacts, and de- duced the corrections to the American Ephemeris and the British Nautical Almanac, respectively. In the former, Leverrier's old the- ory of Mercury is used; and in the latter, his later tables; and the importance of the comparison lies in the circumstance that these lat- ter include a term due to the supposed attraction of an infra-Mercu- rial planet. The mean corrections to the predicted times of contact resulting from the observations are as follows: s. s. 1st contact, C ob. corr. to Am. Eph. 45.7 to N. A. 4 2d " 15 " " - 61.8 " -20 3d " 11 " " -124.4 " -18 4th " 10 " " -141.7 " -35 Means - 1)3.4 -40.25 Thus it appears that the later tables, with the term due to an intra- Mercurial planet, give a satisfactory representation of the fact. The apparent corrections to the Nautical Almanac range from 10 s to I s for first contact; 32 s to 10 s for second contact; 26 s to 4 s for third contact; and 41 s to 24 s for last contact. Taking simply the discordances from the mean in each case in the tables given by Mr. Boss, the mean error of an observation is 2 s for first contact, 6 s for second, and 5 s each for third and fourth. Considering the small number of observations of first contact, we should not be far wrone in taking the mean error as about the same for all four contacts, and equal to 5 s . Micrometrical measures of the diameter of Mercury during the transit gave 11.30"0.14", uncorrected for irradiation or possible expansion of the screw. This value would give 176. G s as the inter- val between external and internal contact. The observed interval was 172.4 s between first and second, and 171.2 s between third and fourth. PHYSICS OF THE GLOBE. By CLEVELAND ABBE, Of the Aeaiy Signal, Office. THE EARTH.* INTERNAL CONDITION. Professor H. Hennessy read before the British Association, at Dublin, an important paper on the Limits of the Hypoth- eses regarding the Properties of the Matter composing the Interior of the Earth. He maintains that the views long ago proposed by himself, in opposition to Hopkins, are those that now are coming to be generally accepted : that the mathe- matical investigations of Hopkins, Thomson, Darwin, etc., have little or no bearing upon the question, because these authors have assumed an incompressible homogeneous fluid nucleus to be surrounded by a solid elastic compressible shell; whereas we now know that the fluid nucleus is vastly more elastic than its rocky envelope a reversal of conditions that entirely changes the problem. He finds evidence in the most recent writings of Thomson and Darwin of these more correct physical views. A comparison of the diverse views of modern scientists upon the condition of the interior of the earth is given by Dr. F. Toula, in a lecture published in Vienna. In a recent address, Sir G. B. Airy inferred from observa- tions on internal temperature, and from the phenomena of hot springs and volcanoes, that " a large proportion of the interior of the earth is fluid and hot," and that this is sur- rounded by a solid crust of varying thickness and density, traversed by cracks which afford opportunities for volcanoes to burst forth where the crust is thin. * Prepared with the assistance of Prof. C. G. Rockwood, of Princeton, N. J. 92 ANNUAL RECORD OF SCIENCE AND INDUSTRY. UNDERGROUND TEMPERATURE. The report of the British Association Committee on Under- ground Temperature, by Professor Everett (Nature, vol. xvii., p. 470 ; American Journal of Science and Arts, III., xvi., p. 134), gives results of observations, on a very elaborate scale, at Schemnitz, in Hungary, and also in England and in India. The former series was undertaken ill response to a request from the Secretary, in 1873, to the Imperial School of Forests and Mines at Schemnitz, and was carried out by Dr. Otto Schwartz. It consisted of observations in no less than thirty-eight galleries connected with six shafts of the mines. Comparisons were made between the temperature of the deepest gallery of each shaft and the assumed mean an- nual temperature of the ground at the shaft-mouth, and also between the deepest and the shallowest observation in each mine. The result of the former was an average increase of 1C. for 41.4 meters, or 1 Fahr. for 75.5 feet; of the latter 1 C. for 39.8 meters, or 1 Fahr. for 72.5 feet. The mean of these two would be 1 Fahr. in 74 feet. The report brings out inci- dentally the important variations of rock temperature, which may arise from the decomposition of metallic sulphides as pyrites, the disturbing effect of which needs to be guarded against. The English observations were made at Boldon Collierv, between Newcastle and Sunderland, in two holes bored upward to a distance of 10 feet from some of the deep- est seams. The results indicated, for the interval between the two holes, a rate of increase of 1 Fahr. in 3 7 feet; and for the whole depth from the surface a rate of 1 Fahr. in 49 feet. The Indian observations, published in the JRecords of the Ge- ological Survey of India, vol. x., part i., were made in 1875, under very satisfactory conditions, in a bore 310 feet deep, at a place named Manegaon. The results indicate an average increase of 1 Fahr. for G8 feet. Professor Everett has suggested a method of observing temperature in filled-up bores by a sort of modified thermo- pile. Two wires of different metals as iron and copper hav- ing been joined at both ends and covered with gutta-percha, except at the junctions, were to be placed with one junction buried in the bore, and the other above ground. Then a gal- vanic current would be generated in the wire whenever the PHYSICS OF THE GLOBE. 93 two junctions were exposed to different temperatures; and by regulating the temperature of the outer junction until a galvanometer indicated no current, that of the buried junc- tion would be known. This is essentially the method em- ployed by Becquerel for many years past. {Nature, vol. xviii., p. 505.) Sir William Thomson {Philosophical Magazine, May, 1878, p. 370) proposes several problems regarding the conduction of heat through rock, the principal of which is this : "A fire is lighted on a small portion of an uninterrupted plane boun- dary of a mass of rock, of the precise quality of that of Cal- ton Hill, and after burning a certain time, is removed, the whole plane area of rock being then freely exposed to the at- mosphere. It is required to determine the consequent con- duction of heat through the interior." The mathematical discussion leads him to a series of conclusions which may be found stated at length in the American Journal of Science and Arts, III., xvi., p. 132. The temperatures in the St. Gothard Tunnel have been ac- curately observed by the engineers, and their observations discussed by Stapff and Hann. They, however, can give little or no reliable information as to the temperature of the earth in its interior, and the whole of our present knowledge on this subject is thoroughly unsatisfactory. Mr. William Morris, of Earl's Hill Colliery, publishes an earnest remonstrance against accepting temperatures of the ground as observed in coal-mines, as having anything to do with the temperature of the earth at that depth. Such fig- ures, according to him, are wholly dependent on the ventila- tion of the mine. The temperatures of the spring-waters for two different springs in Tokio, Japan, are given, apparently by Knipping, in the last number of the Mittheilungen of the German-Asiatic Society for each month of the years 1873 to 1877, and from these he deduces a table for the correction to reduce any month to the mean of the year. These corrections he has then applied to observations of springs in other portions of Japan, from which he deduces the mean temperature for the year. The influence of artificial coverings and of shade upon the temperature and moisture of the soil form the subject of a 94 ANNUAL RECORD OF SCIENCE AND INDUSTRY. volume by C. Wolling, whose investigations of this subject are, we believe, almost the only ones at present accessible, and form a portion of his work "On the Influence of Cover- ing, etc., etc., on the Fertility of the Soil," Berlin, 18V 7. The temperature observations were taken at 8 A.M. and 5 P.M., at G .A.M., and 2 and 10 P.M., for three years at depths of one tenth of a meter, or about 4 inches. Wolling finds that during the warm season the ground that is shaded by plants or otherwise is colder than the fully exposed : the daily vari- ations are considerably less. In cold weather the snow-cov- ered earth is considerably warmer than the naked earth : its temperature changes are less decided. The earth freed from all stones larger than peas is in summer slightly cooler than that on which large stones are allowed to remain, but in win- ter is slightly warmer. The temperature changes are greater in the latter kind of earth, since at the time of the daily max- imum the temperatures are higher, and at the time of mini- mum are lower. Messrs. Ayrton and Perry communicate to the Philosoph- ical Magazine the results of an elaborate determination of the heat conductivity of stone. The methods of experiment occurred to them during the lectures of Sir William Thomson in Glasgow, in 18 74, and admit of highly accurate results. The results bear directly on the accuracy of Fourier's equa- tion for the flow of heat in solids of poor conductivity. The authors acknowledge their indebtedness to the Japanese stu- dents of the Tokio College of Eno-ineerino- for assistance in their work. The distribution of heat in a homogeneous spherical shell, whose surfaces have a temperature varying with the time, has been studied as a mathematical problem in an inaugural dissertation by Dr. P. Langer, of Jena. He elucidates many details in a problem whose general solution has been already treated of by Fourier, Poisson, and Riemann, and a modifica- tion of it by Neumann. The temperature of the earth at St. Petersburg and Xukuss has been discussed in a memoir by Wild. The observations were made with an apparatus similar to that of Lamont. The observations at Xukuss were made by Dohrandt, with a sim- ilar apparatus, thrice daily for two years; and the tempera- tures close to the surface were also observed every two hours, PHYSICS OF THE GLOBE. 95 day and night, during eleven and a half months. These lat- ter observations are, so far as he knows, the only complete ones that have ever been made anywhere for the determina- tion of the daily period of the earth's surface temperature. His discussion of the diurnal variation, with his numerous references to preceding works, constitutes a very important addition to our knowledge. The theory of Poisson gives a very crude approximation to the truth, on account of the dis- turbances introduced by rainfall, air currents, etc. By comparing his results for Nukuss with the observations at Melbourne, he finds that both the daily minimum in the temperature of the air and that for the surface of the earth occur almost simultaneously, namely about sunrise; but the maximum occurs in the earth sensibly earlier than in the air. According to the theory, however, the difference should be even greater than is found by observation, so that the maximum temperature on the upper surface of the earth should occur only a short time after midday. In order to reduce observations of the earth's surface for diurnal varia- tion, a table of corrections is given for such combinations of hours as ordinarily occur. In discussing the annual varia- tion of temperature, he shows that the observations of the thermometer lying upon the earth's surface are an important addition to the series, not only on account of their direct practical bearing on vegetation, but especially for their the- oretical bearings, as enabling us to determine the thermal constant. The irregular variations in the earth's temperature could scarcely be determined from the five years of observation hitherto treated of; but a parallelism with the air tempera- ture is shown to exist. The absolute mean temperatures of the ground are for both places found to be very materially higher than the tempera- ture of the aii*. At 3 meters depth the temperature is at St. Petersburg so much higher than it is at the surface as to show the presence of a large disturbing cause, probably the water of the Neva. The next chapter of Wild's work is an exhaustive collation, discussion, and criticism of all ob- servations of earth temperature made by twenty-two previ- ous observers, which is followed by recommendations as to the best method of determining earth temperatures. His 96 ANNUAL KECOKD OF SCIENCE AND INDUSTRY. summary of his results is too lono: to be given here. We need only endorse his expression of the importance of obser- vations immediately above and below the earth's surface, and of hourly observations at a number of stations in Amer- ica, as well as other parts of the world. In connection with the subject in the previous paragraph, we call attention to a novel application of our knowledge of earth temperatures, to be found in the recent report of the U. S. Entomological Commission, p. 431, where Mr. Abbe at- tempts to estimate beforehand the amount of heat received up to any given date by the eggs of the Rocky Mountain locust, which are usually deposited in a warm, dry, soft soil from 1 inch to i an inch below the surface. In executing this work, which was published before receiving the above-men- tioned memoir of Wild, Mr. Abbe made a large collection of data relating to the diurnal variation of the earth's tempera- tures, and by assuming a mean value appropriate to the dry soil of the West, has prepared a table of predicted dates, which agrees well with the observed dates of the hatching of the grasshoppers. VULCANOLOGY. Under the title of "Vulcanologische Studien" (Wien, 1878) Dr. Edward Reyer has published a memoir in which he dis- cusses the nature of the materials which remain in a volcan- ic vent after the eruptive action has ceased, and the features presented by those volcanic cones which are formed by the quiet outwelling of liquid lava. The same author in his " Beitrage zur Physik der Eruption- en," published in 1877, discussed the part which the demon- strated capacity of various substances in a state of igneous fusion for absorbing certain gases may have in accounting for many of the phenomena of volcanoes. A. II. Everett shows (Nature, xvii., p. 200) that the im- pression is erroneous which regards the island of Borneo as having for ages represented an area of entire quiescence, near- ly encircled by an active volcanic belt. Four recent earth- quakes in the island are noted one in 1874 and three in 1876. And the existence of thermal springs, in association witli ba- saltic rocks, and the frequent occurrence of igneous rocks are thought to indicate an outbreak of volcanic activity in com- paratively recent geologic ages. PHYSICS OF THE GLOBE. 97 Professor Doelter, of Gratz, has reported to the Vienna Academy of Sciences upon the extinct volcano Monte Ferru, in Sardinia. Professor F. W. Clarke discussed the alleged volcano at Bald Mountain, N. C, before the American Association for the Advancement of Science at St. Louis. The Rev. Samuel Haughton and Edward Hull delivered in 1875 a joint-report, but recently received by us, to the Royal Irish Academy on the chemical, mineralogical, and microscopical character of the lavas of Vesuvius from 1631 to 1S68. Twenty specimens were examined chemically by Haughton, who shows that augite is always present in the maximum possible quantity ; second, that magnetite is pres- ent eleven times out of twenty in the minimum possible quantity; third, that leucite is present only once in the max- imum possible quantity; fourth, the minerals always present are, 1st, felspathic leucite, nepheline, or sodalite, anorthite; 2d, hornbUndic augite, magnetite; fifth, the antagonistic minerals by examination afford some clue as to the process of formation of the lavas. Mr. Hull, in his microscopical ex- amination, particularly speaks of the beauty of the struct- ure revealed when we examine thin sections of these lavas. With polarized light the general field of view is converted into a dark groundwork, in which crystals of augite, horn- blende, mica, and olivine now transmitting the richest tints of crimson, green, and bronze, which rival the ruby, the em- erald, and the topaz are conspicuously set. SEISMOLOGY. Professor C.W, C. Fuchs has published his Statistical Ac- count of Eruptions and Earthquakes for 1877. He notes 5 volcanic eruptions and 109 earthquakes. The latter were distributed as follows: in the winter months, 33 ; in the spring months, 31 ; in summer, 11 ; and in autumn, 34. The notices of American Earthquakes, by Professor Rock- wood, are continued by a list of 54 shocks, in the American Journal of Science and Arts, III., xv., p. 21. An important historical paper upon Japanese Earthquakes was read before the Asiatic Society of Japan, by I. Z. Hattori, A.B. (Rutgers College), now of the University of Tokio. The author has collected from the native records notices of E OS ANNUAL KECOllD OF SCIENCE AND INDUSTRY. numerous shocks, of which 149, which lie has classed as de- structive, were tabulated as follows: 1 in 5th century. 1 " 6th " 7 " 7th 7 " 8th 28 " 9th 11 in lOtli century. 10 " 11th 1 " 12th 7 " 13th " 8 " 11th " 15 in 15th century. 8 " IGth 15 " 17th " 13 " 18th " 1G " 19th Also, taking the 11th, 12th, and 1st months of the Japanese old calendar as cold months, the 5th, Cth, and 7th as hot, and all the others as mild, he finds during the fifteen centuries 28 great earthquakes in the cold months, 47 in the hot, and 72 in the mild; or 75 in the extreme seasons, and 72 in the mild seasons, the difference being only three. He describes an an- cient Chinese seismograph, invented by Choko in 132 A.D., whose indications were recorded by an officer of the govern- ment. The Observatory of the University at Tokio is now provided with a Palmieri's instrument, with which the shocks now oc- curring; are recorded. Considerable attention has been given this year to the earthquakes and volcanoes of Japan. The memoir by Hat- tori, just referred to, was read March 23, and is published in full in the Transactions of the Asiatic Society of Japan, vol, vi., p. 249. It was followed by interesting remarks by Professors Veeder and Ayrton, Hon. Dr. Murray, etc. Profess- or Ayrton stated that he found in Mr. Hattori's data evidence of periodicity in the destructiveness of the earthquakes. This paper was followed on May 11 by one by Mr. George Cawley on Constructions in Wood and Stone and their Relative Suit- ability for an Earthquake Country like Japan. His conclu- sions are in favor of properly proportioned brick and stone buildings, and against the customary wooden Japanese struct- ures : however he would not -ht- time the temperature varies with altitude in an entirely dif- ferent manner from what it does by day. The most important work on atmospheric temperatures received during the year is the first part of Wild's "Tem- peratur-Verhaltnisse" for the Russian Empire, which great work will eventually include all questions relating to the distribution of temperature throughout Asiatic and Europe- an Russia. The present volume is confined to the prepara- tory work of collecting and criticising the material at hand, and especially to the investigation of the diurnal tempera- ture periods, as shown by series of hourly or other frequent observations. Wild declines to present the laws of diurnal variations in the form of the Lambert formulas, and confines himself to the graphic method of plotting and interpolation by means of free-hand-drawn curves. The reasons for this important step are fully and forcibly given, and consist in the utter insufficiency of the Lambert formulae to represent the observations unless from eight to sixteen terms are em- ployed, which leads to great and unnecessary labor, and even then introduces erroneous times of maximum and minimum. Wild concludes this portion of his work with a series of 100 ANNUAL KECOliD OF SCIENCE AND INDUSTRY. twelve generalizations in reference to diurnal temperature changes. Among the conclusions he deduces from these, we note that he deems it entirely premature to elaborate any formula for the connection between the diurnal period and its apparent physical causes, the solar radiation, atmospher- ic diathermancy, soil, winds, clouds, etc. Elaborate tables for the reduction of observations made at various hours to the true daily and annual means conclude this first portion of Wild's important work. The expense of compiling these tables has been borne by the minister in charge of the crown lands. Tables of mean annual temperatures for numerous points in Colombia and Ecuador arc published by Reiss and Stiibel in the tables of altitudes determined by them in those coun- tries. The twenty-five years of unbroken observations from 1848 to 1872, at twenty-nine stations in Germany, have been, by Hellmann (Zeitschrift K. P. StatistiscJien Bureaus, vol. xv., p. 405), made the basis of an inquiry into the Variability of the Temperature in Northern Germany. The highest mean variability occurs in Eastern Prussia; the least variable cli- mate is that of the northern coast of the Baltic. The aver- age variability of the summer months is only half that of the winter months. The most variable month is February; the reason of which is found, by Hellmann and Dove, in the fact that at that time the waters of the Arctic regions are still frozen up. A highly suggestive table gives the number of years necessary to be employed in order to obtain a mean that shall have an accuracy of one tenth of a degree, whence it appears that three hundred years of observations would be needed to obtain this accuracy in the mean for the most va- riable month, or February. Hann has communicated to the Academy of Sciences of Vienna a memoir on the Temperature of the Air observed at that place during the last hundred years, in which work he has simply completed a task left unfinished by Jelinek. lie investigates the secular change and the annual changes, and especially the relation between the temperature and the sun-spots, in reference to which latter subject he concludes that the influence of the sun-spots upon the mean tempera- ture is so slight that within any given eleven-year cycle it is PHYSICS OF THE GLOBE. 167 completely obscured by other influences, and that even in the mean of nine cycles there is no certain evidence of any definite relation ; to which conclusion Celoria had also come in 1874, in reference to the temperatures of Milan. Hann has also investigated the possibility of predicting the temper- ature of any given season of the year from the known temper- ature of the past season. He concludes that, on the whole, when the temperature of any season is decidedly greater or less than the normal temperature, it is more probable that the following season will deviate in the same direction from the normal. Similar results have been obtained by Quetelet and Eisenlohr. In conclusion, he reduces the temperatures hitherto observed in Vienna to the localitv of the new Mete- orological Institute, on the Hohewarte, near Vienna. In a subsequent paper on this same subject, Hann revises his method of determining the mean temperature, inasmuch as he considers that he may have been led into error by having given too great weight to the long series of observations made unfortunately with somewhat less perfect instruments and under an objectionable exposure. The direct utilization of the solar heat for industrial pur- poses a subject which has been diligently pursued for many years by Mouchot forms the subject of a note by him read before the Academy of Sciences, September 30, 1878, in which he says that his smaller pieces of cooking apparatus have never failed to work during sunny weather. Some mirrors of less than half a square meter, constructed with all desira- ble perfection, have sufficed to roast half a kilogram of beef in twenty-two minutes, and to cook, in an hour and a half, stews which required four hours of an ordinary fire of wood ; and in half an hour to bring three fourths of a liter of cold water to the boiling-point, which latter corresponds to the utilization of 9.5 colories per minute per square meter a re- markable result in the latitude of Paris. The solar alembics have also furnished equally excellent results. Assisted by Pifre, he had completely set up, on the 1st of September, a solar receiver, whose mirror presents an aperture of about twenty square meters. Of the innumerable inventions of the venerable John Erics- son, he is, we believe, most fond of his inventions and research- es relative to caloric and solar engines, and the direct utili- 1G8 ANNUAL RECORD OF SCIENCE AND INDUSTRY. zation of solar heat. A work published by Mouchot, in 18C9, "La Chaleur Solaire et sur Applications Industrielles," gives a rather complete exhibit of all that had been done up to that time in France, and some notice of the life-work of Ericsson. But the Centennial Exhibition gave Ericsson him- self a proper occasion to collect and review his imposing ar- ray of works in this department, beginning, we believe, with 1825 or thereabouts. These he has published, at his own ex- pense, in a luxurious work, in which he reproduces much of what he has elsewhere published, and adds much more new and critical matter. The work is invaluable to one who would follow the author in his long career, and would under- stand the merits of the questions at issue between him and many other investigators. MOVEMENTS OF THE ATMOSPHERE. In a mathematical discussion of the movements of the wind, M. Finger, of Vienna, finds that, in consequence of the earth's rotation, any movement of air along the surface must affect the barometric pressure. Easterly winds increase the pressure, and westerly winds diminish it. Eugene Suttor, honorary engineer, of Belgium, contributes to the Royal Institute of Luxemburg, vol. xvi., a memoir on the Movement of Bodies on the Surface of the Earth, taking into consideration the diurnal rotation of the latter. His work is apparently independent of those which have been published the past few years by several investigators; and lie applies his formula? simply to explain the phenomena of the Foucault pendulum, and the observations, by Reich, on falling bodies, at Freyberg. An inaugural dissertation of T. Bertran, at the University of Marburg, 1S76, has come to hand rather late in the day, on the subject of the Motion of a Material Point, under the Influence of Gravity, upon a Surface of Rotation having a Vertical Axis. After the general equations of motion have been given, he considers especially cylindrical, spherical, and paraboloid surfaces. Attention should be called to an article, by J. Aitken, in the Philosophical Magazine, on Rigidity produced by Cen- trifugal Force. This subject has been treated of by Sir Will- iam Thomson theoretically, and by Osborne and Aitken ex- PHYSICS OF THE GLOBE. 169 penmen tally. The latter illustrate the subject by investi- gating the movement of a chain hanging loosely over a pul- ley, around which it is rapidly running. The various curi- ous curves into which it twists itself are fairly explicable by a proper application of the laws of centrifugal force, and the elasticity and rigidity that are imparted to the chain by its motion remind one of the properties of vortex rings of air or water. The allied mechanical principles here involved will, it would seem, also find an application in some phenomena of meteorology, especially those of tornadoes. These views were first communicated two years ago by Aitken to the Royal Society of Edinburgh, but have only recently been published. The students of vortex motion will find some valuable chapters in the last volume of the Proceedings of the Royal Society of Edinburgh, which, although delivered in 1875, have only come to hand the past year. The first paper, on Vortex Statics, by Sir William Thomson, concludes with a brief statement of the general propositions, definitions, and principles. The paper itself deals with the steady motion of vortex rin^s. The cases are considered in which one circu- Jar vortex ring is linked with another, and where three or more rings are mutually interlinked ; the cases of trefoil knots, nine-leafed knots, and much more complicated figures are also considered. Further papers on the same subject are also promised. At the reunion of French scientists at the Sorbonne, Pro- fessor Hebert, of Mulins, read a paper on the General Move- ments of the Atmosphere. From the Signal Service tri-daily weather-charts he concludes that the Atlantic storms have their origin in the Rocky Mountain district, being produced by the friction of the equatorial current against the moun- tain-tops. These tourbillions follow the river-courses to the Gulf of St. Lawrence, and there form the great depressions which start across the Atlantic ; and we need hardly say that Mr. Hebert's conclusions differ widely from the views held by American meteorologists. A contribution to our knowledge of the effect of winds on the gradient of rivers (and inversely to the friction of wind over water) is given in a paper, by W. H. Searles, on the Levels of Portions of the Erie Canal. lie finds the probable error in 136 miles of most careful levelling to be 0.103 foot. H 170 ANNUAL RECORD OF SCIENCE AND INDUSTRY. The Science Observer, the organ of the Boston Amateur Scientific Society, contains notes by Henry White, calling at- tention to the importance of observing meteor trains as a means of learning something about the air-currents at high altitudes. The importance of such observations is not to be denied ; but unless several observers at well-located posi- tions unite in such observations, we fear that but little can be deduced relative to air-currents. Were a few persons, located within fifty miles of each other, to systematically ob- serve and compare notes on the motions of cirri, polar bands, and meteor trains, they would soon be in position to materi- ally contribute to meteorology. Observations on the direction of the motions of clouds con- tinue to attract increased attention. Besides the apparatus invented by Goddard, Braun, Linss, and others, Marie Davy describes the following, which he has established in the gar- den of the observatory at Mont Souris. It consists essen- tially of a horizontal mirror upon which the sixteen principal compass points are engraved. The observer places his eye so that the image of the cloud appears in the centre of the mirror; he then sets a small cone upon the mirror in such a position that the point of the cone covers the same centre. A few minutes afterwards he brings his eye to the same po- sition, and easily sees in what direction the cloud has moved. Linss has observed the motions of the clouds at Darmstadt with his improved form of Braun's nephoscope. He finds that the apparent velocity of cumuli, pallio-cirri, and cirro- cumuli is greater at 8 A.M. than at noon or 4 P.M. Pie finds a constant relation between the directions of the higher clouds as compared to cumuli, and that the changes in the upper strata of air occur at least four hours earlier than in the lower ones. The first publication of Dr. Ilildebrandsson on the Move- ments of the Upper Currents has been followed by the pub- lication, at Upsala, of an "Atlas des Mouvements Superieurs." Besides this, Rev. Clement Ley has published a series of maps for each day of March, 1S7G. His studies make it prob- able that the stratum of air in which cirrus-clouds occur is at a much higher level over the advancing portion of the cy- clone than over its rear. In addition to their memoir on the Distribution of Tempera- PHYSICS OF THE GLOBE. 171 tu re in the Air, Professors Guldberg and Mohn have also pub- lished a short elementary essay on Vertical Currents in the Atmosphere. They treat of ascending and descending cur- rents, and illustrate their formulae by numerous examples, and especially urge the importance of knowing more than we do about the condition of the outer, or higher, atmosphere with reference to temperature and moisture. The relative force of the wind at the ground, and at a con- siderable elevation above, has been studied by J. Stevenson, C.E., of Edinburgh. The observations give in each case a great increase in velocity, but hardly allow of further definite generalization. The experiments on the velocity upon differ- ent sites of a round tower, and between various screens, are very interesting, and show how very local are the indications of an anemometer, and how carefully its site should be selected. BAROMETRIC PRESSURE. In order to determine the mean barometric pressure at the new Meteorological Observatory at Vienna, Hann has inves- tigated all the barometric observations made in that city since 1775, but finds the uncertainty of the instrumental er- rors and the altitudes such that it is not advantageous to combine them with the recent observations; and therefore relies entirely upon those made since 1852. He closes his paper by deducing the diurnal and annual periodical changes in the pressure. Buys-Ballot communicates a highly important memoir con- taining tables of monthly mean pressures at the stations for which the departures are given daily in the Meteorological Bulletin of the Netherlands. The large number of stations, and the careful revision of the data, render this a very wel- come addition to our knowledge of the distribution ofatmos- pheric pressure in Europe. He has also published, in the Aus- trian Meteorological Journal, a table showing the annual bar- ometric variations for 108 stations throughout Europe, as re- sulting from long series of observations, and reduced to a uniform decennium. The discussion of his results he reserves to himself in a future number of his Jaarbooeh. Carpmael, of Toronto, gives a formula for the reduction to sea-level of the readings of the barometer. His formulae are convenient, and quite as accurate as the conditions of the 172 ANNUAL RECORD OF SCIENCE AND INDUSTRY. problem admit of; they differ, however, very much from those of the method adopted by the Army Signal-Office. His table is especially adapted to be used with the arith- mometer of Thomas de Colmar. Dr. Woeikoff communicates to Petermann's Mittheilungen some of the most recent results of the Russian Levelling Ex- pedition into Siberia, under the command of General Von Stubendorf. His results are considerably higher than those previously accepted, and show us that the mean pressure in the interior of Asia, when reduced to sea-level, is decidedly higher than has been generally supposed. These results con- firm his previously announced generalization that in northern latitudes the atmospheric pressure is higher over the conti- nents than over the sea. This excessive pressure over the continents he refers to the well-known fact that the conti- nents are especially cold in winter, and, on the average, cold- er throughout the year than the ocean; whence follows an anti-cyclonic movement of the winds, and an excess of clear sky and barometric pressure. The diurnal variation of the barometer, as deduced from twenty years' photographic records, at the Royal Observato- ry, has been communicated to the Meteorological Society of London. Rykatcheff announces the existence of a third diurnal bar- ometric maximum, which is especially evident between lati- tudes 40 and 45 N. and in the month of January ; it occurs at about one or two o'clock in the morning. In order to de- tect its presence at any station, it is necessary to have actual hourly observations throughout the night. It seems to be equally obvious at stations in Europe, Asia, and North Amer- ica, and does not exist in the tropics. In reference to a third daily barometric maximum, Kar- linski writes that his twenty-five-year record at Cracow con- firms Rykatcheff's announcement, but only for the month of January, and even then only in the faintest trace. He adds that from 52 to 87 averaging 70 barometric waves annual- ly pass over Cracow. Linss, of Darmstadt, calls attention to the importance of considering the inertia of the atmosphere (Lamont's theory) in explaining the diurnal barometric variation. In studying the direction of the motion of the clouds, he finds that the PHYSICS OF THE GLOBE. 173 barometer rises less in proportion as the angle is larger which the direction of the lower clouds' movement makes with the direction of the barometric gradient. Dr. W. Koppen, of the Deutsche See warte, calls attention to the fact that Professor Erman,in 1853, in PoggendorfF's An* nalen, vol. lxxxiii., proved that the direction of the wind Avas inclined to the barometric gradient in accordance with the law now frequently, but wholly erroneously, called Buys-Ballot's law. Furthermore, he shows that Dr. Dippe published in 1860 a still more elaborate investigation into the relations between isobars and winds, and determined the angular deviation, and also the strength of the wind, in terms of the gradient. The present writer has previously called attention to the fact that Buys-Ballot's law, as enunciated by him, is simply a rule for predicting the winds in Holland, and is not at all a general physical law of storms. The inclination of the winds to the isobars was elaborately worked up by James Henry Coffin, and published in the Proceedings of the American Associa- tion for the Advancement of Science, 1 853 ; while in the same year Rev. Humphrey Lloyd deduced the angle between the winds and the radius drawn to the centre of the system of winds. The physical explanation of the laws of the winds is due to Ferrel, whose first publications date 1856, although lie had then for some years perceived and taught the cor- rect views. An important memoir, by Hofimeyer, is published in the Zeitschrift of the Austrian Meteorological Society for Octo- ber, on the Distribution of Atmospheric Pressure over the North Atlantic Ocean during the Winter, and its Influence on the Climate of Europe. He prefaces his remarks by reference to Buys-Ballot's law, and to the researches of Ley, Ferrel, Mohn, Guldberg, Loomis, and Broun. As an improvement on the charts of isobars published by Buchan and WoeikofF, he gives tables and charts based upon a much larger num- ber of observations, which, he thinks, must be recognized as the most reliable that can be produced at present. According to this new chart, for January, the principal i minimum for the North Atlantic is to the southwest, and not to the northeast of Iceland; while a partial minimum extends from this point towards the North Cape on the one hand, and towards Davis Strait on the other hand. 174: ANNUAL RECORD OF SCIENCE AND INDUSTRY. In order to improve on these charts, lie proposes to extend his daily weather-charts by extra- and interpolation over those portions of the ocean from which he lias no direct ob- servations, and to combine into monthly means the readings taken from his daily charts. At present he has charts for only two years IS 74 and 1875 which he gives, and which, of course, show a distribution of pressure decidedly different from that given in his general chart. The charts are also given for December, 1874, and February, 1875 ; that for De- cember showing a very remarkable departure from what would be considered a normal distribution. He seems to consider that three minima namelv, that of Davis Strait, that northeast of Iceland, and that southwest of Iceland by varying their position and relative develop- ment, alternate in their control over the winds and weather of the Atlantic. The character of the weather which prevails over North- ern Europe depends, therefore, entirely upon the predomi- nance of one or other of the barometric minima of the North Atlantic Ocean. While recognizing the fact that, theoreti- cally, the wind affects the distribution of pressure, he seems to only partially appreciate the importance of the law estab- lished by theoretical mechanics namely, that it is not so much the barometric pressure that determines the wind, as it is the wind that determines the pressure. lie recognizes the fact that the area studied by him is but a very small portion of the northern hemisphere, and that the causes of the important variations in the distribution of pressure must be, at least in part, looked for outside of the region covered by his maps. In this respect, certainly, the monthly maps published by Ferrel in 1877, and the daily weather-maps of the northern hemisphere published by the Signal-Office in 1878, must be recognized as the first steps in the proper treatment of this subject. EVAPORATION AND PRECIPITATION. "Weilenmann, in the Schweizerischen Met. J3eob., 1877, vol. xii., gives the development of a formula for the quantity of evaporation, which agrees, in the most remarkable manner, with observations at Vienna, St. Petersburg, Mont Souris, 1*01:1, and Tiflis. This memoir and his essay on Atmospheric PHYSICS OF THE GLOBE. 175 Temperature constitute two important contributions to de- ductive meteorology. Professor Nipher sends us, among the publications of the Missouri Weather Service, a valuable table of monthly, an- nual, and seasonal amounts of rainfall observed at St. Louis, principally by Dr. George Engelmann, from 1834 to 1877. There are but few stations in the world that can present an unbroken homogeneous series like this, and it is to be hoped that similar tables may be published for such other long se- ries of observations as we may have in the United States. Such a collection, supplementary to the Smithsonian Tables, would be useful in many investigations. A paper, by Otto Krummer, on the Distribution of Rain- fall in Europe, is published in the July number of the Jour- nal of the Berlin Gesellschaft fur Erdkunde. Dr. G. Hellmann has published, in the Xetherlands mete- orological Jaarbooel', a work on the Humidity and Cloudi- ness of Spain and Portugal. He gives the hourly variations for 4 stations, and the monthly and annual means for 18 sta- tions, for 12 years. The average number of cloudless days during the year is, for Obiedo, 50; Saragossa, 199; and Va- lencia, 260. The distribution of rain over Germany, according to the four seasons, is almost exhaustively treated of by Dr. J. Van Bebber, in Petermann's Jlittheilungen, and is accompanied by four charts, showing isohyetals for each 25 millimeters. He distinguishes, for Germany, three well-marked regions: first, the west coast, or region of heavy autumnal rains; sec- ond, Alsace, the region of heavy winter rains; third, the re* gion of summer rains, which includes pretty much all the rest of Germany. An investigation, by Dogiel, published in Vol. XX. of the Bulletin of the St. Petersburg Academy, into the innumera- ble forms of the hexagonal crystals of iodoform (CHI 3 ), af- fords additional reasons for careful investigation into the circumstances that determine the formation of the varieties of snow-crystals. It is highly probable that definite temper- atures and pressures may be indicated by these forms. The large number of observers of rainfall in India will sur- prise every one who has not especially looked into this mat- ter. The government supplies rain-gauges to all districts and 17G ANNUAL RECORD OF SCIENCE AND INDUSTRY. subdivisions. They are also generally placed at every plant- er's station, and at the tea-gardens, under the control of the various tea companies. Several provinces have more than 100 gauges each, and in all India there are estimated to be at least 1500 rainfall stations. This subject was brought to notice by the reading of a pa- per, by C. N. Pearson, on the Meteorology of Mozufferpoor, Tirhoot, India (Quarterly Journal of the Meteorological So- eiety, 1877, p. 410). An extraordinary rainfall of 14 inches iu 12 hours occurred between midnight of the 22d of Septem- ber, 187G, and the following noon, and measures at seven neighboring places showed the local nature of the rain. Returns from 900 rainfall stations in France are published quarterly by the Association des Sciences de France and the Departement de Pouts et Chausses under Belgrand. Mr. Nathan Butler communicates to the Jjulletui of the Minnesota Academy some notes on a hail-storm which he ex- perienced in the western part of Minnesota on the 18th of Au- gust, 1858. The sky was generally clear, the weather quite warm, and the clouds overhead very light and fleecy. Im- mediately following a flash of lightning, large hailstones be- gan to fall, and continued for perhaps two or three minutes. They buried themselves for about half of their diameter into the sod of the prairie. When the shower was finished, the stones were sprinkled into the ground about fifteen feet apart, and the larger ones were about the size of a man's two fists. In shape they were spherical on one end, made up of hexag- onal crystals, like crystals of quartz ; the other end was coni- cal, made up of white ice. They were quite solid, and did not break in falling. They were found to weigh a pound each. The abnormal character of the weather of the winter of 1877-78 is strikingly seen in the immense floods of the Sac- ramento valley. It is probable that such floods may occur every century. The enormous erosions west of the Rocky Mountains may be due to such occasional floods quite as much as to any regular annual rainfall. A very complete synopsis of the various theories with re- gard to the formation of hail is given by Dr. T. II. Baucrmeis- ter in successive numbers of Dr. Klein's excellent popular scientific journal (Jaea, He reviews the history of the sub- ject from the time of Musschenbroek, and gives especial at- PHYSICS OF THE GLOBE. 177 tention to the views of Volt a, Leopold Von Bach, Muncke, Mohr, Reye, Lucas, Baumgartner, and Dellmann. He con- cludes, however, by saying that previous to any critical dis- cussion of these different theories, it is, above all, necessary that there should be as full as possible a collection and short description of all hail-storms that have been scientifically ob- served with reference to the form of the clouds, the direc- tion of the wind, the atmospheric electricity, the topograph- ical distribution, as well as a collection of the results of sci- entific balloon voyages, and as many as possible observations on high mountains. He hopes in a short time to collect such material, and will gladly welcome any contribution. Reynolds has considered the formation of hail-storms, and has artificially reproduced them in great perfection. STOKMS. Professor Loomis has published his eighth contribution to meteorology, January, 1878, and his ninth paper in July, while the tenth paper is understood to be in press, having been read before the National Academy in October, 1878. The eighth paper deals with the origin of areas of low press- ure, and the ninth paper considers especially those storms that come from the Pacific coast eastward to the Mississippi valley.. He then takes up the areas of high barometer. Combining the two studies with the observations of the clouds, he arrives at a general circulation of the atmosphere similar to the views published by Ley, Hildebrandsson, etc. The important memoir of Captain Henry Toynbee on the Meteorology of the North Atlantic during August, 1873, has been published by the Meteorological Council. This work re- lates especially, of course, to the history of the great hurricane of that month, and does not appear to have been prompted by the report of Mr. Abbe on the Nova Scotia hurricane, but to have been begun in December, 1873, quite indepen- dent of, and before the publication of, that work. Captain Toynbee has collected some 280 ships' logs, and has utilized all other sources of information ; so that his work is undoubt- edly the most valuable collection of facts relating to any hurricane which has ever yet been published, and is really a monument to his patience in collating material which, judg- ing from our own experience, must have offered very many II 2 178 ANNUAL RECORD OF SCIENCE AND INDUSTRY. perplexing discrepancies. His work includes 31 daily charts of the North Atlantic and a concluding synoptic-chart, while his text presents us with a review of each daily chart in suc- cession, followed by a series of chapters on the hurricane, and conclusions that can be drawn from the study. He states that from the 1st to the 10th, the northeast trade and southwest monsoon were often in close proximity over that part of the sea which lies to the southwest of Cape Verde. It seems most probable that the hurricane was form- ing on the 12th in about 11 N. and 20 W. From that time on, the track of the centre of the hurricane is occasion- ally indicated until the 17th, from which date until the 25th its track is very clear as it passed westward between the West Indies and the Bermudas, and then turned northward, and finally northeastward, near the southern coast of Nova Scotia. On the 2Gth he concludes that the centre of the hur- ricane was south of Newfoundland, but that it was broken in force, and that contact with land broke up the great eddy, which had shown no signs of breaking up so long as it was over the open sea. From the 27th to the 31st there appear areas of slight barometric depression between Labrador and Europe, attended occasionally by strong gales but no hurri- cane. By means of these depressions, which represent the breaking-up of the hurricane, the meteorologist wonjd con- tinue the track of the hurricane eastward to Great Britain; but the practical seaman would say that the hurricane, as such, died out in Newfoundland. He shows that had we tel- egraphic communication with the Bermudas and St. Thomas, timely warnings might have been sent to Nova Scotia and the United States. The law according to which areas of low pressure in Europe pass outside of, instead of advancing into, areas of high pressure seems to have also prevailed in the progress of this hurricane. The important question with regard to the direction of the wind and the bearing of the centre of the hurricane is elu- cidated by diagrams, and especially by measures made on three different charts, and at distances from 100 to 800 miles from the centre. On these charts the angle between the bear- ing: of the hurricane-centre and the direction of the wind has been carefully measured for 108 different ships' positions, the average of all of which shows that the wind does not PHYSICS OF THE GLOBE. 179 make an angle of 90 with the bearing of the centre, but that there is an indraft of from 25 to 31, beins; on the average 29, or 2-| points. It is probable that there is really a great rano-e in the amount of indraft, so that this mean is a rouoh approximation to the truth. The best rule for navigators is, he thinks, about as follows: In the northern hemisphere with the wind North, the hurricane centre probably bears E.S.E., or more southerlv. East, " " " " " S.S.W., " westerly. South, " " " " " W.N.W., " northerly. West, " " " " " N.N.E., " easterly. The only modification of the ordinary instructions for han- dling ships in hurricanes which these facts suggest is, that when the circular theory states that a ship ought to run be- fore the wind, these facts show that, if possible, she ought in the northern hemisphere, to keep the wind well on the star- board quarter. He also shows that the indraft is greater in one quarter of a hurricane than another, and greater near the centre than farther from it. The mean of the three charts just mentioned gives an average wind force of 10 on Beau- fort's scale, at a distance of 90 miles from the centre, and a force of 6 at a distance of 425 miles from the centre. In the chapter on the normal circulation of air during Au- gust, 1873, lie introduces a very suggestive letter from Clem- ent Ley, with reference to the relations between the upper and lower currents of the atmosphere circulating round areas of barometric depression. Mr. Ley has evidently established inductively, from the consideration of a great number of ob- servations, certain laws of atmospheric circulation which have been theoretically and more or less vaguely guessed at by several meteorologists of the past generation. His diagram represents two low areas, With a high between, all advancing due eastward. The lows are preceded by southwest to southeast and northeast surface winds, which are also ascending winds, and are accompanied by clouds, either cumulus, stratus, or cirrus, above which he represents descending currents from the northwest and southwest, which "feed the preceding area of low pressure, and produce an area of clear skv. The advancing: edcre of a bank of cirro-stratus cloud is very well marked, and he states that he has in his diagram given its mean position in relation to the isobar and 180 ANNUAL RECORD OF SCIENCE AND INDUSTRY. the upper and lower currents, as deduced from a great num- ber of distances. He concludes with a strong appeal to owners, captains, and officers of vessels to assist him in further studies of ocean meteorology. In an appendix he gives a comparison of wind observations at Pike's Peak and Mount Washington. Mr. H. F. Blanford communicates to Nature, July 25, a short chapter on the Genesis of Cyclones, in which he dis- tinctly combats the idea that these may originate between parallel and opposite currents of air. He regards the tor- rents of rain over the cj^clone cradle as furnishing the ener- gy of the incipient storm. Lieutenant J. Spindler publishes, in an appendix to the St. Petersburg Daily Meteorological Bulletin, a valuable collec- tion of the Paths of Storm-centres that have passed over Northeastern Europe during 1873 to 1877. The tables and re- sults will afford material for testing future theories of storm movements. An abstract of this valuable paper is also given in II aim's ZeitscJtrift. The hurricane of the 23d of September, 1877, on the coasts of Venezuela, is briefly described in the November number of the Gazeta Cientifica. This hurricane formed in the im- mediate neighborhood of the island of Trinidad, moved near- ly northward to Cuba, and reached the central portion of the United States. The article on the West India Hurricane of September 12 and 13, 1876, by Tejeda, of Porto Rico, which was referred to by us in the Annual Record for 1877, has, we learn, been re- printed in the Annuaire, for 1877, of the Spanish Xavy De- partment, with apparently considerable additions. The cy- clone moved from St. Christopher over Porto Rico, and final- ly reached Florida. In the Paris Comptes Rendus, Faye claims that Hirn has favorably considered the theory according to which the air in a cyclone is descending instead of ascending, and that he allows two kinds of descending cyclones the ordinary whirl- wind and the tornado. In April, Professor Ferrel read before the National Acad- emy at Washington a memoir on the Theory of the Tornado and Water-spout, in which he gave the formulae connecting the pressure in the interior of the whirl with the elevation PHYSICS OF THE GLOBE. 181 above ground, the temperature, humidity, and velocity of the air, and the dimensions of the moving mass. His formulae were illustrated by numerous examples, and are believed to present us with the first satisfactory deductive investigation of the subject that has as yet been published. The famous squall of March 24, 18*78, in which the Euryd- ice was capsized, has been made the subject of a short study by W. Clement Ley, who thinks that this squall may be re- garded as a typical one, in that the longest diameter of its barometric depression was nearly at right angles to the di- rection of the wind; and very much exceeded its shortest' diameter. In one respect it was decidedly exceptional namely, in the backing of the cirrus current by about 112 during its passage. Mr. Ley concludes that the principles of cloud observation should occupy a very large place in the education of seamen, and, we may add, of all other meteorological observers. It does ncrt seem possible for a central meteorological office to predict such local squalls as this, but it is allowable to infer from Ley's article that experienced navigators can them- selves foresee them a few minutes in advance, sufficient to prepare their vessels to meet them. Bucchich communicates to the Austrian Association re- sults of numerous observations at Lesina on water-spouts. He states : first, their cause is to be found in opposing wind- currents; second, at Lesina they always move from east to west; third, the direction of rotation of the whirl is opposed to that of the hands of a watch ; fourth, for one water-spout he was able to determine its time of rotation namely, twelve seconds. An account of the tornado of the 15th of May, 1878, in the Department of Vienna, is given by Touchimbert in the Paris Comptes Hendus. While making magnetic observations at Kirksville, Mo., Professor Nipher had occasion to carefully observe several dust-whirls, or small whirlwinds. One of these whirls crossed a pond of water, and immediately a depression was formed, extending to the bottom of the pond; the top of the depres- sion was about six feet in diameter. The water all around this depression was whirling rapidly. K. V. Riecke has collected and studied the statistics of 182 ANNUAL RECORD OF SCIENCE AND INDUSTRY. hail-storms and resulting damages in AViirtcmbcrg durins the thirty years from 1828 to 1857, the work being a continu- ation of that previously published by Camerers. He gives interesting quotations from early chronicles dating back a thousand years, which have, we understand, been reprinted in previous Jizhrbuchers published by the Wurtembcrg Sta- tistical Bureau. The average number of hail-storms is 14.8 per year during the first half of the period investigated by Riecke, but only 12 in the latter half of that period. The years of most frequent hail-storms were, 1852 (? 2G), 1847 (24), 1834 (23), 1835 (23), 1873 (22), 1839 (20). The average area covered by the hail that fell from these storms is 2525 morgens, or 790 hectares, or 1907 acres. By summing up the areas covered by hail, it is found that the years of maximum area were, in regular order, 1873, 1872, 1853, 1852, 1869, 1856, 1830, 1846, and 1832; and the years of minimum area were, 1833, 1851, 1858, 1844, 1857, 1874, 1835, 1848, 1842, and 1840. A strong indication is given of an increase in the intensity of thunder-storms. Besides nu- merous interesting historical notices dating back to the year 855, Riecke gives detailed tables of the hail-storms and of the property destroyed during the last fifty years. The summer of 1878 was remarkable for numerous hail- storms in Great Britain. The severest occurred on the 4th of August in Leicestershire, and is well described by W. Clem- ent Ley, who states that about two inches of hail fell in his neighborhood in fifteen minutes, the stones averaging about five inches in circumference, as measured two hours after they fell. In the Bulletin of the Natural History Society of Col mar, G. A. Hirn supports in part the theory of Faye as to the nat- ure and origin of cvclones and tornadoes. Among the terribly destructive storms of modern times must be included that of April 12, on the Chinese coast. This storm passed directly over Canton, causing indescribable de- struction and an immense loss of life, estimated at between 6000 and 7000 persons : it appears to have been, at least in Canton, of the nature of a tornado, having a diameter of about 300 yards, and a path of destruction only 3 miles long. General T. L. Rosscr gave a short address in December, 1877, before the Minnesota Academy of Social Science at PHYSICS OF THE GLOBE. 183 Minneapolis, on Tornadoes and Cyclones, in which he en- deavors to explain the phenomena of a shower of flesh, or ba- trachian spawn, that occurred on the 3d of March in Bath County, Ky., and concludes by propounding a theory of the general movements of the atmosphere. He states that on the line of the Northern Pacific Railroad between Bismarck and Fargo, a distance of about 200 miles east and west, the storms of severe north or northwest winds, with snow, ad- vanced eastward at an average rate of about 12 or 15 miles per hour. When a storm is reported as beginning at Bis- marck, the weather at Fargo would often be bright and beau- tiful, but as the storm approached, scattering clouds here and there appeared, and considerable agitation would be manifest in the upper regions of the atmosphere. As the storm rose from the west, the winds would suck in from the east, exhib- iting the remarkable (?) phenomenon of a storm coming up in the face of the wind. Professor S. A. King has furnished the daily press with a graphic account of his balloon ascension in August, 1875, at Burlington, Iowa. He started at about half- past four, at which time there was a terribly ominous-looking thunder- storm approaching. His balloon had been filled at the gas- works, two miles distant from the place of ascension, and had lost so much of its gas that its diminished buoyancy obliged him to start alone. His balloon, from the moment it left the ground, was rapidly carried towards the coming thunder- storm, and its ascent was also rapid until, in about seven min- utes, he entered the cloud. Going up through this, just as he expected to reach the top there came right down in front of him, and apparently not more than fifty feet distant, a grand discharge of electricity. In an instant, almost, he felt the car lifted, the gas in the balloon suddenly expanded to overflow- ing, and the balloon was hurled through the cloud with in- conceivable velocity, the car swinging back and forth at a terrible rate. All this was suddenly accomplished, and would have been quickly over, but before the car had time to stop oscillating, another discharge of electricity occurred, and the same thins: recurred again and again, until it seemed as though he should never escape. Each time the balloon would be extended to its utmost, until, finally, it was thrown into the midst of the tremendous rain, and was carried down rap- 184 ANNUAL RECORD OF SCIENCE AND INDUSTRY. icily. Gradually the gas was forced out, and the lower part of the bag doubled up into the upper part, forming a sort of parachute. He landed just twelve miles from his starting- place, having evidently retraced a portion of his track. ATM< >SPUERIC ELECTRICITY. An important work of Edlund on the Origin of Atmospher- ic Electricity is published by the Swedish Academy, and also in the London, Dublin, and Edinburgh Philosophical Maga- zine, and in Hann's Zeitschrift. He shows that the rotating magnetic earth, being a good electric conductor, must, by unipolar induction, give rise to a nearly uniform charge of negative electricity throughout its own whole mass, but to a variable charge of positive electricity throughout the at- mosphere. The discharges, of course, give rise to aurora and lightning. He deduces, with comparative accuracy and simplicity, the diurnal and annual periods, and the geograph- ical distribution of these phenomena. Important papers by Angot in the Annuaire of the Mete- orological Society of France, and by Everett in the report of the Permanent Committee of the Vienna Congress, present the best connected accounts of modern methods and theories that are at present accessible to ordinary readers. In a note on the Origin of Thunder-storms, Professor Tait explains how a pair of vertical rotating columns revolving in opposite directions can be produced out of one column in the upper regions of the atmosphere revolving about a horizontal axis. He also suggests that the source of the electricity spe- cially developed in thunder-storms may probably be found in the contact of air with the surface of the warm drops of water. A general review of the subject of Atmospheric Electricity is given by Dr. Margules in the Vienna Zeitschrift, wherein lie expounds the electrical principles that occur, and enumer- ates some of the questions that first demand investigation. The phenomena of Globular Lightning are described by M. Fitzgerald, of Donegal County, Ireland, who saw a globe of fire in the air descend gradually along the crown of a ridge, and down into the valley, where it drifted along a boggy sur- face, occasionally disappearing in the soil, but reappearing farther on. It finally flew across the stream, and buried it- PHYSICS OF THE GLOBE. 185 self and disappeared in the peat bank. Its total duration was about 20 minutes. It appeared about 2 feet in diameter at first, but gradually diminished to 3 inches. The sky was clear at the time. Wherever it touched the ground in its course, it ploughed up the earth to a depth of several feet. In the discussion on this report, Mr. Symons stated that forked lightning and globular lightning were, he thought, the same. The Scientific Gazette for Venezuela publishes a communi- cation to the Physical Society of Caraccas, by J. M. Tebar, on an Electric Phenomenon peculiar to Lake Zulia, called the Farol cle Maracaibo. He explains this light as being an electric phenomenon due to a quiet discharge of a large extent of atmosphere of the negative electricity with which ascend- ing currents of air are saturated, while the descending cur- rents are charged with positive electricity. The same jour- nal contains an original theory, accompanied by some math- ematical demonstrations, relative to the Nebular Hypothesis, by E. Ricard. Hildebrandsson has published an Investigation into the Thunder-storms of Sweden, based on observations at about 250 stations, from 1871 to 1875. He distinguishes between the thunder-storms that attend the advancing sides of ex- tensive storms (the Wirbelgeicitter) and those that originate in overheated districts (the Wcirmegewitter). Similar classi- fications have been made by Mohn in Norway and Fron in France, and are occasionally alluded to in the weather reviews of the Army Signal-Office. Scarcely a single instance was recorded in the five years in which it could not be shown that the so-called "heat" or "sheet" lightning was simply the reflection of lightning so far distant that the thunder was inaudible, or possibly refracted above the observer's ear. Dr. Pissis publishes in his "Physical Geography of the Re- public of Chili" some notes on thunder-storms in that state. Destructive thunder-storms are unknown in the inhabited portions of the state, but are of daily occurrence among the mountains. In the morning a small cloud forms around eacli summit, which soon increases to a large cumulus, and event- ually extends over the whole range of peaks. In the after- noon fearful thunder and lightning occur; and, high np the mountain-sides, snow and hail. The hail and snow are phos- phorescent, as it were, with electricity. The storms on the 1 SO ANNUAL KECOHD OF SCIENCE AND INDUSTRY. eastern slopes of the Ancles and on the pampas are of shorter duration than on the west side. The lower horizontal sur- face of the clouds, which is at an altitude of 1500 or 2000 meters, sometimes extends from the coast eastward to far beyond the Andes. The greatest thunder-storms in Chili last three or four days, but the electric discharges all occur in the first hour. Carl AVeyprecht has published the "Magnetic and Aurora Observations of the Austro-Hungarian Arctic Expedition of 1872 to 1S74," with which he also gives an excellent analysis and resume of our knowledge on the subject. Among other things, he strongly inclines to the opinion that the auroral light belongs to the lower portion of the atmosphere. He fails to establish any connection between the aurora and the weather. He concludes that the zone of maximum frequency moves northward during the winter, and again southward during the spring. Thalen has a memoir on Exploitation for Iron Ore by Means of the Magnetic Needle. He gives full and strictly accurate methods, and his formula? may possibly be applica- ble to the search for the seat of the disturbances that accom- pany auroras. An elaborate paper on the Protection of Buildings from Lightning, by Dr. Mann, is republished, with additional notes, in the sixth volume of the "Professional Papers on Indian Eno-ineerin2;." The American Academy of Sciences of Boston has instituted an inquiry with reference to the general phenomena of light- ning, and, among other things, has requested the Chief Signal Officer of the Army to collect, as far as possible, all notes and observations upon accidents caused by lightning. All who may read this note are cordially invited to record such facts as mav come to their knowledge. The Proper Method of Protecting Buildings by Lightning- rods is discussed, in a fifth note, by Melsens, in the Brussels Bulletin, 1878, p. 43. lie gives an analysis of the conditions necessary to insure efficacy, and discusses the constructions published by the French Commission. According to Mr. Symons, both Mishel, Secretary of the French Commission on Lightning-rods, and Jarriant, a large dealer in lightning-rods adopt as the area protected from PHYSICS OF THE GLOBE. 1ST lightning by a given rod a circle whose radius is If times the height of the rod above the building. An excellent paper on Lightning-conductors was read before the British Association, by Mr. R. Anderson. He states that so slow has been the march of progress since the days of Benjamin Franklin, that lightning-conductors are still wanting on at least half, and perhaps two thirds, of all the public buildings, and on 95 per cent, of all the private houses in Great Britain. The terrible losses occasioned by lightning are due to three sources of neglect: first, not pro- viding any lightning-rods at all ; second, not placing them in the right position ; third, not having them regularly tested, so as to ascertain their constant efficiency. Lightning-con- ductors, he says, ought to be tested at least once a year. Between three and four thousand pounds sterling were spent in protecting the Houses of Parliament some twenty years ago. Since that time they have never been tested, and there is no guarantee whatever that a discharge of lightning may not at any time fall upon the Queen's throne. The testing should take place at regular intervals. The wonderful sensitiveness of Bell's telephone such that it responds to induced currents of the strength of only the one thousand-millionth part of a C. G. S. unit, or less gives it great importance as an instrument of research in relation to atmospheric electricity and terrestrial ground -currents. Some observations made in Providence, II. I., have led to the conclusion that by it the existence of a thunder-storm may be detected when otherwise altogether invisible at the station. The Edison microphone has even been applied successfully to the observation of subterranean sounds produced by vol- canic actions, and may evidently be further applied to what- ever goes on in the earth and ocean. Mr. Henry Goldmark, of the Laboratory of Harvard Col- lege, contributes observations upon the Effect of Temper- ature on Atmospheric Electricity. He used Sir William Thomson's water-dropping apparatus and his quadrant elec- trometer. The observations were made in a room whose temperature could be varied as desired. He found, first, that even a very considerable change of temperature does not have any great or marked effect upon the electric potential 188 ANNUAL RECORD OF SCIENCE AND INDUSTRY. of the air; second, that, however, a rise in temperature does produce a slight but constant increase in the potential. OPTICAL PHENOMENA. Montigny gives a preliminary chapter of results of his ob- servations on the Scintillations of the Stars. The first inter- esting observation that he publishes is in the Bulletin of the Royal Academy at Brussels, 1878, p. 157. It was first no- ticed by Usher, 1788, at Dublin, that the stars scintillate re- markably during and preceding an aurora. In 1840 Arago says that Forbes and Neckar and himself agreed that the stars never scintillate unless there is an aurora somewhere. Montigny observed an especial increase of scintillation of auroras April 5, 1870, and June 1, 1878. He also says that the scintillation is connected with a lowering of temperature, and that this cooling occurs simultaneously with auroras and. scintillation, and that, finally, the cooling causes the scintillation. In the second communication, in the Bulle- tin, Brussels, vol. xlv., p. 391, he gives the results of Seven Years' Observations with his Scintillometer on Fifteen Stars as to Color, and finds that the red colors predominate during dry weather, while the blue precedes rain. The memoir on the Connection between Scintillation and Rain, etc. {Bulletin, 1878, p. 598), is received too late to allow of the extended notice that it deserves. A memoir by Wild (St. Petersburg Bulletin, vol. xxi.,p. 312), on the Photometric Determination of the Diftuse Light of the Sky, gives the preliminary results of an investigation that for many years has engaged his attention. The instrument that he has invented and used for this purpose he designates as the urano-photometer, and it seems to combine the feat- ures of the photometers invented by Arago, Hirn, Wild, and Zollner. A disk of ground glass illumined by the sun af- fords an artificial standard light, whose whiteness is turned to the required shade of blue by receiving it through a quartz plate and polarizing apparatus. Wild finds (1) the color of the diffuse sunlight, as we proceed from the sun northward on a vertical circle, changes gradually from the red to the violet end of the spectrum, and at a distance of 80 from the sun is nearly between Fraunhofer's lines C and D, or at the wave- length 0.000G28 meter; from here onward to the horizon the PHYSICS OF THE GLOBE. 189 tint retreats to the red end ; (2) the color and the polariza- tion have their maximum at 90 from the sun ; (3) the total intensity of the diffuse reflected skylight appears to be least at about 80 distance from the sun, and diminishes thence more slowly towards the horizon than towards the sun. In some papers on Physical Science for Artists, Mr. Lock- yer introduces an explanation of the color of the skv, and some criticisms on some prominent pictures in the Royal Academy, which will be generally interesting to artists. The lunar eclipse, August 12, 1878, was studied spectro- scopically by N. Maunder, at Greenwich, who observed a marked absence in aqueous lines, apparently showing that there was comparatively little vapor or cloud in that part of our atmosphere through which the sun's rays passed. The atmospheric bands were also remarkably faint. At the Dublin meeting of the British Association for the Advancement of Science, we notice anions the meteoroloai- cal papers one by Professor S. P. Thompson, on the Wedge- shaped Radial Streaks of Light devoid of Color observed* between the Primary and Secondary Bow of the Rainbow. An article on the History of the various Theories of the Rainbow, by Reclam, is published in Gaea. He especially touches upon the theories of Newton, Descartes, and those who preceded them. The Bulletin of the Geographical and Statistical Society of Mexico, vol. iv., p. 190, gives a detailed account of a So- lar Halo at Zongolica on the 27th of April, 1874, a very rare phenomenon in that latitude, and on that account worthy of note. The connection between tempests and solar spots has been studied by Zenger. He also finds that photographs of the sun taken in the Tyrol and in Switzerland are surrounded by peculiar haze and halos, which are not otherwise visible to the naked eye, indicating the presence of moisture and haze very high up in the atmosphere, and anticipating the occur- rence of storms sometimes by ten or fifteen days (? hours) (see the Franklin Institute Journal, 1878, p. 283). Mr. Burton has made some observations on the Spectra of the Zodiacal and Auroral Lights. He used an apparatus loaned by the Royal Irish Academy of Sciences, and Profess- or Stokes, commenting upon the paper as a valuable one, says 190 ANNUAL RECORD OF SCIENCE AND INDUSTRY. that lie seems to have shown that the bright line thought by Angstrom to be identical in these two lights is really not so. Mr. Burton has also measured the position of a new dark band in the zodiacal light, in which light he also finds dis- tinct traces of polarization. MISCELLANEOUS RELATIONS AND APPLICATIONS. Sun-spot Periods. A memoir of exceptional thoroughness and interest upon the Sun-spot Periods in our Atmospheric Phenomena is by P. G. Halm "Ueber die Beziehungen der Sonnenflecken-Pe- riode zu meteorologischen Erscheinungen," Leipzig, 1877. Dr. S. Guuther, in a work on the " Influence of the Celes- tial Bodies upon the Weather" (Nuremberg, 1876), gives an excellent historical resume and bibliography of this sub- ject. The discovery by Main at Oxford that the annual mean direction of the wind fluctuates with the variation of the solar spots has stimulated Hornstein to a similar investiga- tion for Prague. He has communicated to the Vienna Acad- emy, June, 1877, a memoir on the Probable Dependence of the Mean Direction of the Wind upon the Period of the Sun's Spots, the study of which subject has occupied him since 1871. His results are similar to those of Dr. Gould, whom he appears to have anticipated somewhat, and with whose methods his own agree very closely. He finds an increase of 0.00133 C. for a diminution oft on Wolf's scale of solar spottiness. Dr. B. A. Gould contributes to the Ast. Nach. a summary of his climatological researches. From the observations at Buenos Ayres and Bahia Blanca, since 1856 and 1866 respec- tively, he has computed for each year separately the thermal wind-roses, as also the mean temperatures and mean direc- tion of the wind. By means of the thermal wind-roses he is able to reduce the mean annual temperatures to what they would have been if the mean annual direction of the wind were the same throughout the series of years. He thus ob- tains mean annual temperatures which are apparently per- fectly intercomparable, and finds that these figures follow the changes in sun-spots remarkably closely. He finds that a fall of 1 C. in the mean annual temperature corresponds PHYSICS OF THE GLOBE. 191 at Buenos Ayres to an increase of 138 on Wolf's scale of solar spottiness, and at Bahia Blanca to an increase of 193 on Wolf's scale. Fritz contributes to Peterraann's Mittkeilungen a memoir, in his well-known exhaustive style, on the Periodical Changes in the Lengths of Glaciers. A glacier is a very delicate meteoroscope, and the changes in its volume and length, de- pending upon a combination of several circumstances, enable ns, as it were, to integrate the meteorological conditions of the year. Professor Fritz suggests even that through them we may find a new bond of connection between solar spots and terrestrial meteorology; and, in fact, finds most remark- able coincidences between the hundreds of cases that he has collected and the dates of sun-spot maxima and minima. With an increase of sun-spots comes an increase in the length of the glacier. Perhaps the most interesting contribution to this subject is that given by Professor H. Fritz in his study of the peri- odicity of the rise and fall of the Nile, as recorded on the nilometer of the island of Rhodes. He had at his disposal only the record of the highest reading on the nilometer for each year from 1825 to 1872, and he shows that these follow Wolf's sun-spot numbers with most unexpected closeness. The years of minimum sun-spots are nearly coincident with the years of least rise in the Nile, thus confirming Meldrum's results for the southern hemisphere. It is to be hoped that it may become possible to similarly investigate the mean dis- charge as well as the maximum heights of the Nile. That this periodicity was known to the ancient Egyptian priests is rendered plausible when Ave recall Joseph's prediction of seven full and seven lean years, corresponding to the seven years of high-water and low-water, and agreeing closely with Fritz's table of periodicity. In Vol. XX. of the Vierteljahrsschri/t of the Natural His- tory Association of Zurich, Fritz has an essay on the Longer Periods of the Auroral Phenomena, in which, among other things, he, as the first who, in 1863, fully demonstrated the parallelism of sun-spots and auroras, very plainly protests against having been ignored, but copied by Loomis in his famous essay of 1866. In the present work, by a new and improved method of analysis of a vastly larger collection of 192 ANNUAL KECORD OF SCIENCE AND INDUSTRY. data, Fritz shows that the aurora maxima occur 0.73 of a year alter the sun-spot maxima, while the aurora minima oc- cur 0.30 year before the spot minima. These small devia- tions from absolute coincidence may, however, possibly be due to the imperfections of our data; the auroral changes are much more energetic than those of the sun-spot frequen- cy. There is good evidence of the existence of a period of 5 x 11.11=55.55 years, and Fritz even suspects one of 220 or 222 years' duration. The subject of the connection between rainfall cycles and sun-spot cycles has called, forth considerable correspondence, much of which is noticed in JSTature, where articles have ap- peared by Dr. "W. W. Hunter, Dr. E. Bonavia, C. Meldrum, A. Buchan, and S. A. Hill. The general result of these investigations is, we think, quite decidedly favorable to the conclusion that the solar spots and temperatures change in parallel cycles, and affect every feature in terrestrial meteorology. The subject can only be properly studied by including ob- servations from the whole earth in an analysis, and we are not surprised to find that Mr. Hill has shown that the data for India can be twisted into proving either a maximum or a minimum of rain for each maximum of solar spots, the truth being that a change in the solar heat produces opposite ef- fects in two regions whose geographical conditions are dis- similar. Dr. Hunter has shown that at Madras itself the years of little rain, drought, and famine agree with the years of mini- mum sun-spot frequency. Messrs. Hill and Archibald have discovered that in Northern India, between latitudes 20 and 30, the winter rainfall corresponds inversely with the period of solar spots i. e., the maximum winter rainfall coincides with the minimum of sun-spots. The failure of these winter rains causes short crops and severe famine in the subsequent season. Assuming that the sun radiates less heat at times of sun-spot maximum, it seems possible to plausibly explain the consequent slight rainfall, In general, in years of maxi- mum sun-spot, the summer rainfall is above, and the winter rainfall below the average, and inversely in years of mini- mum sun-spot. The reality of this connection is endorsed by Buchan, who appeals to the British government to avert dis- PHYSICS OF THE GLOBE. 193 astrous famines by instituting a comprehensive system of hy- draulic engineering, such that the surplus rains of one season may be husbanded for use in time of need. Perhaps the greatest boon possible to confer upon Ceylon and India will be the restoration of the ancient system of tanks and irrigation, by which, a thousand years ago, the des- olating effects of a scarcity of water were almost complete- ly averted. Similar tanks will, at some future day, doubtless be introduced into our own western country. Mr. Meld rum read a memoir before the British Association at Plymouth, showing that the number and severity of the cyclones in the Indian Ocean during 1875, 1876, and 1877 had been much below the average, and entirely confirmed the hypothesis of an eleven-year cycle. Mr. O. A. Derby, of Rio Janeiro, communicates to Nature for August 8 a table of Rainfall in Tropical Brazil, showing that the relation between rainfall and sun-spots, as deduced by Dr. Hunter for India, holds good also for Brazil. In Nature for September 26 are two important papers by C. Meldrum and F. Chambers respectively; the former dis- cusses Rainfall at Madras, Edinburgh, and Paris, and the lat- ter discusses Barometric Pressure at Bombay. Both make out a series of remarkable parallels between sun-spots and terrestrial meteorology. The latest communication on this subject is from J. A. Broun, in Nature, November 7, where he enumerates several conclusions bearing on the researches of Chambers and oth- ers. With regard to the question of the generality of their results, he concludes first, years of greatest and least mean pressure are the same for all India ; second, the apparent re- lation to the decennial period, found by Mr. C. Chambers for Bombay, holds good for all India. Professor M. Williams, in a letter to the London Times of November 7, states that "from his observations of the pres- ent condition of the disk of the sun, in connection with vari- ous atmospheric phenomena, the Madras astronomer Pogson prophesied, in 1876, a recurrence of the drought and famine that occurred in 1877 hh 5' Mr. C. Meldrum has distributed some copies of his article on Sun-spots and Rainfall, extracted from the Mauritius Al- manac and Register, in which he gives a connected account I 194 ANNUAL RECORD OF SCIENCE AND INDUSTRY. of his own and other researches into this subject. These re- searches now include every portion of the world, and, accord- ing to Meldrum, the rule is almost universal that the years of greater rainfall are the years of greater sun-spot area. In India the irregularities seem to be very great, partly owing to the imperfections of the observations and to the great cli- matic variations, and possibly in part to the empiric and ob- scure nature of the theory. However, the parallelism is com- parable in regularity to the diurnal variation of the barome- ter or the periodicity of the aurora. Professor G. F. Becker contributes to the Mining and Sci- entific Press, of San Francisco, of February 2, some tables and diagrams illustrating the periodicity of the rainfall at San Francisco, Sacramento, and Stockton since 1849. He finds evidences of a well-marked thirteen -year period for each place. The Variation of the Zodiacal Light in Sympathy with the Sun's Spots is the subject of a short note by Hind, who quotes a letter of Olbers, published in 1839, wherein the va- riation of the zodiacal licrht is mentioned. Modern observa- tions seem to confirm the statement of Cassini, that the zo- diacal lio-lit is much more brilliant when numerous and larffe sun-spots are present. The Annuaire of the Bureau of Longitudes for 1878 con- tains, as an appendix, a memoir by Faye, on Cosmic Mete- orology, in which the distinguished author seeks to give a strong proof of the influence of solar spots and other cosmic influences. A criticism of this work, by John Allan Broun, is published in Nature, vol. xviii., p. 128. Health. An excellent address of Dr. Schreiber, on Meteorology in Medicine, has been translated by Dr. W. II. Geddings, and published in the Richmond and Louisville Medical Journal. Some Notes on the Climate and History of New Mexico, by Dr. Thomas A. McParlin, are published in the "Smithso- nian Report for 1877." He gives the views of numerous au- thors on the theory of the influence of hig-h altitudes on hu- man life, and his memoir is full of miscellaneous interesting statistics, including also a letter from J. M. Gough on Elec- tric Disturbances on Telegraph Lines. In reference to the PHYSICS OF THE GLOBE. 195 effect of altitude, lie states that his own experience has been that he has never detected any quickening or other disturb- ance of respiration, and that at the greatest altitudes as yet attained by man it is evident that there is an abundance of oxygen to supply the needs of the blood at every inspira- tion, while at low altitudes there is great excess of oxygen. This consideration deprives of its force the argument of those who say that the quickened respiration and pulse experienced by most observers is an involuntary effort of the system un- der the control of the sympathetic nerve to furnish a suffi- cient supply of oxygen to the blood. He considers that the human race degenerates by dwelling in low and unhealthy places, and that in such places it is decimated by such pesti- lences as the cholera, yellow fever, remittent fever, and plague. Mr. Buchand has commuuicated to the Philosophical Soci- ety of Glasgow some more recent deductions with reference to the relations of meteorology to public health, as deduced from the study of weekly mortality and weather returns for all the large towns in the British islands. He shows that diarrhoea and British cholera on the one hand, and dysentery and Asiatic cholera on the other, form themselves into two distinct groups. The prominent phases in the annual prog- ress of whooping-cough and scarlet fever agree even to mi- nute details year after year for thirty years. He infers that there is something connected with the weather of spring which tends to reduce the mortality from scarlet fever, but something connected with late autumn weather under which this disease attains its maximum fatality. In the case of whooping-cough, its maximum severity occurs in early spring, and its minimum severity in autumn. In commenting on Mr. Buchand's paper on the Relations of Meteorology to Public Health, Mr. E. M. Dixon stated that, according to the analyses that had been made daily at six points in Glasgow, it appeared that a steady increase in the amount of organic matter in the atmosphere took place along with the increase of temperature in the spring and summer, but that the amount of organic dust decreased as the temperature fell in the autumn. In the Journal of the Franklin Institute for January, Feb- ruary, and March will be found a rather lengthy article, by Professor Brio-o-s, on the Relation of Moisture in Air to Health 190 ANNUAL RECORD OF SCIENCE AND INDUSTRY. and Comfort, in which he maintains that the delightful sum- mer condition of temperature, 62 to GS, and relative humid- ity, 80 to 85 per cent., is not desirable, or even attainable, at oilier seasons in the heating of dwellings, etc. The dry air of America possesses both curative and preventive qualities of great value; moist air that promotes vegetable growth is, on sanitary grounds, not desirable for breathing. The au- thor has found the dew-point far below the freezing-point of Mater in well-warmed and ventilated rooms where there was nothing of that sensation of dryness that is usually held to accompany the heat of a furnace when not supplied with wa- ter for evaporation. New houses, that are accounted un- healthy in Europe, are not so in America. Gas burned in rooms produces much less unpleasant effects in America than in England. What is needed is an equality in relative hu- midity between the interior and exterior air. Thus, if the outer temperature be and relative humidity 40 per cent., and the interior temperature be 70, Ave ought to raise the interior humidity to 40 per cent, by adding a little water, and not to 80 or 90 per cent, by adding too much. The effect of diminished atmospheric pressure upon the hu- man body was discussed by Mermod in the Bulletin of the Switzerland Society of Natural Sciences. His observations extend through three years, and relate mostly to himself: first, he finds that the systematic residence in higher regions is attended by an increase in the pulse, but not in the fre- quency of breathing; second, therefore the ratio between the frequency of respiration and heart-beats grows smaller as we ascend to higher stations; the temperature of the body, however, was unchanged; third, the absolute and relative amounts of carbonic-acid gas can be regulated by moving the patient to a higher or lower level. From an inaugural dissertation, by M. Schyrmunski, of Wil- na, on the Iniluence of Rarefied Air on the Human Body, we extract the following notes as interesting to the invalids who resort to Colorado and other high regions: The first accurate observations on the subject were made by Saussure on the occasion of his ascent of, Mont Blanc in 1787. The princi- pal subsequent observations and publications on this subject have been A. von Humboldt's ascent of Chimborazo; Boussin- gault's ascent of Chimborazo in 1831 ; R. von Schlaginweit's PHYSICS OF THE GLOBE. 197 ascents of peaks in the Himalayas in 1 862 ; and Lortel's "Phy- siologie dn Mai des Montagnes" (1870). The preceding ob- servers ascended mountains. The following: relate to balloon ascensions : Gay Lussac and Madame Blanchard in 1804, both of whom ascended to 7000 meters; Coxwell and Glaisher in 1882 ascended to over 9000 and probably 11,000 meters; and Croce-Spinelli, Sivel, and Tissandier in 1875 ascended to about 8600 meters. From all of these observations, Schyrmunski thinks best to draw but few physiological conclusions, and prefers to rely on experiments made by means of the air-pump. Of similar experiments lie knows only those of Henslaw, Tabarie, Ju- nod, and Vivenot; but in the memoir of the latter on the Physiological Effects of Condensed Air, only two observa- tions are quoted on the influence of rarefied air. He has, therefore, conducted a rather extensive series of experiments upon himself. In each experiment, he or his friends remained in the pneumatic cabinet for two full hours. During this time the rarefaction proceeded uniformly until, in forty minutes, the greatest rarefaction was produced. The pressure then remained constant for an hour, and was then, in about twen- ty minutes, gradually restored to the prevailing atmospheric pressure. The pressure was ordinarily reduced to about 300 millimeters, corresponding to an altitude of about 14,000 feet. He divides lus observations into two classes : first, in so far as they relate to the general effect on the system, they agree with the observations on mountains and in balloons. The first symptom is a sensation of pressure in the ears; the second symptom relates to the voice, which becomes husky and feeble ; but whether this is an effect, of the rarefied air on the vocal organs or the ear he cannot decide. Whis- tling becomes very difficult, due to the altered expiration and inspiration ; headache was very severe in the first experi- ments, and continued for some hours after leaving the cabi- net ; lassitude and inclination to sleep, and a sensation of heat in the face; the lips turned bluish, the eyes burned ; flick- erings and difficulty in fixing the sight; the respiration be- came more and more frequent and superficial, until finally the difficulty of breathing became very great, and the pulse rose from 84 to 104 per minute. All these general symptoms were most decided in the first experiments, and afterwards 198 ANNUAL KECORD OF SCIENCE AND INDUSTRY. gradually diminished in intensity; the most persistent was the effect upon the hearing. Second. In regard to the special effects upon human organism, Schyrmnnski considers first the change in the capacity of the lungs, or the quantity of expired air. Having had considerable experience with the spirome- ter, his observations appear worthy of full credit, and he con- cludes that, in artificially rarefied air in the pneumatic appa- ratus, the vital capacity of the lungs, or the quantity of ex- pired air, diminishes. Its diminution during the process of rarefaction and its subsequent increase appear to be quite reg- ular; the average amount of the diminution is about 2 per cent. He next considers the influence of rarefaction upon the temperature, and finds that there is a slight increase, followed by a steady diminution of the interior temperature of the body a phenomenon which may, perhaps, be explained by the changes in the circulation and respiration ; for at the begin- ning there is an increase in the frequency of breathing and in the pulse, and a rush of blood to the extremities, causing an in- crease of temperature, which is soon followed by slow reaction. From the inaugural dissertation from L. Stembo, on the Physiological Effect of Compressed Air, we take the following notes: After alluding to the contradictory opinions and re- sults of observations of Knauthe, Vivenot, Panum, Lange, and others, he states that his attention was first directed to the vital capacity of the lungs as depending on the barometric pressure. He finds a steady increase in the capacity while the pressure increases, and, on the other hand, obtained a sim- ilar result outside of the pneumatic cabinet. He then inves- tigates any possible source of error affecting his observations, and finds that the increase in lung-capacity is certainly con- firmed. The explanation given by him leads to the conclu- sion that compressed air will have a healing tendency in in- flammations of the mucous membrane of the bronchial tubes; also in acute catarrh of the smaller bronchia 1 , and in bron- chial asthma. With reference to the temperature of the skin under compressed air, he finds that with increasing pressure the temperature invariably sinks. Ilypsometry. At the end of an investigation into the accuracy of his new barometer (Zurich VierteljahrsscJirift,\o\. xx.,p. 385),Weilen* PHYSICS OF THE GLOBE. 199 maim introduces an essay on the Best Time for Determining Altitudes by the Barometer. In continuation of the labors of Ruhlmann, Bauernfeind, Plantamour, and others, he shows that the correct altitude can be deduced from observations on summer afternoons, and that, too, without using the tempera- ture of the upper stations, and even when the stations are at considerable horizontal distances. His method depends on the assumption that the equilibrium of the ascending cur- rents is maintained and expressed by the known laws of ther- mo-dynamics (as developed quite independently by Thom- son, Reye, Hann, and others), and assuming that the ascend- ing currents neither give any heat to surrounding air nor receive any from it or from the sun, or other source. His formula thus deduced, and employing for all his physical constants the numbers ordinarily accepted as resulting from laboratory experiments, enable him to compute altitudes up to 7000 feet, with an extreme error of 15 feet when he uses monthly means of observations in July at 1, 2, or 3 P.M. Lieutenant -Colonel R. S. Williamson, U.S.E., has pub- lished a compendium of his paper on the Use of the Barom- eter on Surveys, which is followed by a comparison of his method with that of Professor J. D. Whitney, as described in his work entitled "Contributions to Barometric Hypsom- etrv." Colonel Williamson claims to have shown conclusive- ly that Whitney's method gives over 40 per cent, more of maximum and mean errors than does his own. Major Powell states, in reference to the hypsometric work of his survey in Southern Utah in 1877, that it rests on a primary base established at Mount Pleasant, at which bar- ometric observations were made four times daily, and were also made hourly for eight days of each month. All his camps and observing-stations were connected with the base by barometric observations; but it is recommended that a special series of hourly observations be conducted for a few years upon some of the Rocky Mountain peaks for the pur- pose of correcting the barometric formula? now in use. For topographic details much use has been made for some years past of the orograph an instrument devised by Professor A. H. Thompson, and which seems to have been lately rein- vented in France. 200 ANNUAL RECORD OF SCIENCE AND INDUSTRY. Physical Geography and Geology. The influence of meteorological phenomena, especially rain- fall and rivers, in altering the physical geography, is well illustrated by the following extract from Markham's chapter on the "Physical Geography of India:" "The basin of the Ganges has been minutely examined by the officers who have constructed the works of irrigation, and the physical laws which regulate the great Indian river-systems have been discussed by Mr. Ferguson. The latter shows that all rivers oscillate in curves whose extent is directly proportional to the quantity of water flowing through them. Water resists water far better than earth does, so that a river can attack its banks in detail and carry the bits away; but still water, by producing a state of rest, forces a river to deposit its silt. Mr. Ferguson concludes, with regard to the Ganges, that from 4000 to 5000 years ago the sea, or at least the tide, extended as far as Kajmahal, and that Bengal proper was a vast bay or lagoon." The gradual raising of the delta is indicated by the positions of the capital cities: thus, 3000 B.C., the only practically habitable part was the water-shed between the Sutley and the Jumna. The first cities really in the plains were Hastanapura, on the Ganges, and Ayodia, on the Gogra, which flourished from 2000 B.C. to 1000 B.C. Then followed in succession Canonj, afterwards Palibothra, or Patna, then Gour, and, finally, A.D. 1604, Dacca. A magnificent chart of Europe during the two glacial pe- riods is published by Petermann, in the twenty-fourth vol- ume of the MittheUitngen, in continuation of his earlier paper on the same subject. Abich contributes a paper on the Glaciers and Snow-lines of the Caucasus. The latter vary from 8000- to 10,000 feet, according to localitv. Observations on the movement of the CD */ glaciers seemed to give negative results. CD CD CD T. Sterry Hunt communicates to the Academy of Sciences at Paris some remarks on the Geological Relations of the Atmosphere. lie says : " I have been led to see in the car- bonic acid discharged from volcanoes and from some springs of gaseous waters, only a product of the decomposition of the carbonates which were previously formed at the surface of the globe, at the expense of the carbonic acid of the atmos- PHYSICS OF THE GLOBE. 201 phere. I have shown, moreover, that the formation of the carbonaceous and bituminous matters in the strata of the earth, all which seem to me to have an organic origin, have required a weight of carbonic acid which far surpasses that of our atmosphere, and moreover would have given place to a very considerable disengagement of oxygen resulting from the deoxidation of carbonic acid and water. It is necessary to admit that this carbonic acid had an extra terrestrial ori- gin. I think we ought to consider our atmosphere as a cos- mic and universal medium, condensed around certain cen- tres of attraction in proportion to their masses and their temperatures, and occupying the whole of interstellar space in a state of extreme rarefaction. From this it will result that the surplus of carbonic acid will be absorbed in equal proportions in the atmospheres of all the celestial bodies, and that at the same time any excess of oxygen disengaged at the surface of our globe will be equally divided among all the celestial bodies. This theory of a universal exchange seems to me to furnish an explanation of the origin of cosmic dust." Botany and Zoology. The influence of atmospheric electricity upon vegetation has been studied by Grandeau, who communicates his results to the Academy of Sciences at Paris, showing that under large trees, under massive shrubbery, and under a coppice covered with verdure, the electric tension of the atmosphere is sensibly zero, while at the same moment, at a iew yards' distance from these conducting bodies, Ave can demonstrate notable quantities of electricity. Berthelot communicates to the Paris Academy some inter- esting remarks in reference to the memoir of Grandeau on the Effect of Atmospheric Electricity. He states that he has discovered that the free nitrogen in the air unites with or- ganic matter under the influence of electricity, not only when strong tensions are employed in the experiment, but also with very feeble tensions. He again calls the attention of mete- orologists and farmers to the importance of the continued ac- tion of atmospheric electricity of feeble tension to the fertili- zation of the soil. The Influence of Temperature on Vegetation was treated of by Goppert, in which he explains why it is that great ex- I 2 202 ANNUAL BECOBD OF SCIENCE AND INDUSTRY. trcraes of cold, lasting but a short time, are less injurious than less extreme temperatures lasting for a longer time. Mid- dendorff concluded from his observations in Siberia that the frozen stems and roots could perhaps exist in that condition for many years without injury, with which conclusion Gop- pert unites his own observation on the revival of vegetation that had been buried for many years under glaciers. He gives an extensive list of plants, and low temperatures which they are able to endure with impunity. Dr. Sorauer communicates to the Botanische Zeitung for January some observations on the Influence of Moisture on Vegetation. He finds that in dry air branching is greater than in moist air, the length of the leaves is less and the breadth greater, and a moist atmosphere is more favorable to the length of leaf-sheaf, to the growth of the principal stem, and also to the development of the root. In dry air the epidermal cells of the leaves were more numerous and broad- er, the cells between the stomata shorter, and the stomata themselves shorter and more numerous than in moist air. Among other papers bearing on the relation between me- teorology and botany, we note a paper by Professor Rein on Mountain and Valley Winds, and their Effect upon the Veg- etation of Volcanic Mountains, read at Cassel. C. Eder, in an inaugural dissertation at the Leipsic Uni- versity, republished by the Vienna Academy of Sciences, in- vestigates the Quantity of Aqueous Vapor Expired by Plants, and concludes that the transpiration is a purely physical process, modified by numerous physical conditions, principal- ly by the relative humidity and the quantity of water the air is able to contain, by the temperature, and by the wind. Light of itself has no influence. There is no periodicity ex- cept as determined by these exterior circumstances. Lauterbur"; contributes to the Basle Association an excel- lent paper on the Influence of Forests upon the Springs and Rivers of Switzerland. Culmann, in some appreciative re- marks, endorses the desire for a system of telegraphic predic- tions of approaching river floods, etc., in Switzerland. The fluctuations in the level of the Great Salt Lake have been especially studied by Mr. G. K. Gilbert, of Powell's Sur- vey, who finds that since 1809 there has been no great change in the water-level, which now averages 10 feet above its level PHYSICS OF THE GLOBE. 203 in 1847. The total area of the water-surface has increased by about 25 per cent., by which expansion the surface for evap- oration was increased. This extension of the lake is shown to be clearly an anomaly in its history, and to explain it Mr. Gilbert states that he has reason to believe that the indus- tries of the settlers have so modified the surface of the land that a larger share of the snow and rain finds its way into the watercourses and the lake. He believes that the tax imposed upon the streams by the work of irrigation is more than repaid by the effects of the draining of marshes and the destruction of herbage and timber. The influence of wind and climate upon the migrations and spread of the grasshoppers has been very fully consid- ered in the reports of Riley and Whitman, State entomolo- gists for Missouri and Minnesota respectively (see also the report for 18*76 of the Commissioner of Statistics for Minne- sota). The report for 1S77 of the United States Entomolog- ical Commission is remarkably full on this point. Hellmann, in Petermann's Mittheilungen, calls attention to the possibility of predicting the invasions of grasshoppers or locusts, which, leaving the Sahara in the spring with south- west winds, are carried over Algeria and Egypt, and do more damage than the severest storms. A similar duty has been frequently urged by Dr. Packard and others upon our Signal Service ; and in this connection it may be well to call atten- tion to a theoretical explanation of the grasshopper migra- tions which has lately been proposed by Abbe, and which is said to account for most of the phenomena that have been observed. According to this explanation, the grasshopper is an insect at home and comfortable only in a rather dry at- mosphere, and possibly a diminished atmospheric pressure ; air that is either too dry or too moist is equally liable to make the insect uncomfortable, and in either case he seeks relief in flight, not knowing whither he shall go. Now the very dry winds are the westerly winds, that bear him rapid- ly eastward to the Missouri and Mississippi valleys. The very moist winds are the south and southeast winds of the Mississippi valley, that bear him or his progeny in the next vear back to his original breedinor-oTounds. It will be curi- ous to show whether this hypothesis holds good for the Af- rican as well as it does for the American insect. 204 ANNUAL KECORD OF SCIENCE AND INDUSTRY. The observations of such meteorological phenomena as af- fect the fisheries continue to be published by the German government, under the supervision of the Commission to In- vestigate the German seas. This prompt monthly publica- tion must greatly facilitate and stimulate the study and util- ization of these data, and naturally suggests the advantages that must result from a regular monthly publication of all meteorological data specially pertaining to the United States fisheries, forestry, injurious insects, etc., etc. The United States Fish Commissioner lias collected an im- mense amount of data relative to water-temperatures, winds, currents, etc., in the United States rivers, lakes, and seas, which will be properly collated. In a memoir on Red Snow, in the " Memoirs of the Acad- emy of Toulouse," vol. vii., Dr. Armieux advances the hypoth- esis that the Uredo nivalis of Bauer, or the JProtococcus niva- lis of Agardh, the Protococcus pluvialis of Cohn, and possibly the Lepraria kermesina of Wrangel are the same ; and that to these spores, in different stages of development, are due the green, red, etc., snows that, in fact, these cryptogams can also live on rocks, in peculiar circumstances, as at Kioulet. Refraction of Light and Sound. Dr. Fabitius, of Kief, shows that atmospheric refractions may be computed for great zenith distances on the assump- tion that the coefficient of refraction is constant quite as well as for small distances. To this end he simply adopts for dis- tances greater than 75 a value of the reciprocal coefficient of refraction increasing in direct proportion with the zenith distance. He hence concludes that the constitution of the highest portion of the atmosphere has but little influence on the horizontal refraction, and that it is sufficient to assume for the upper portion the same law for the variation of temper- ature and density as obtains near the earth's surface. On this assumption he develops the formula) for atmospheric re- fraction, which he is able to express in a series whose succes- sive terms diminish very rapidly, and which are extremely con- venient for the computation of special tables for any locality. The atmospheric refraction has been studied by Professor Kowalski, of the University of Kazan, Russia. With most other investigators, he pays special attention to the law of PHYSICS OF THE GLOBE. 205 diminution of the temperature of the air. The law of this diminution is, according to him, fixed by the mechanical the- ory of heat, and Lubbock, in 1856, was the first to find the solution to this question by starting with the principles of this theory. The present essay dates from 1867, or earlier. By the aid of the mechanical theory of heat, as developed by Thomson and MendeliefF, but with still further generaliza- tions as deduced by himself, Kowalski finds first, during winter the diminution of temperature with altitude is, on the average, very small, and it augments in proportion as the temperature observed near the surface of the earth be- comes higher; second, during the heat of summer the dimi- nution of the density of the layers of air near the surface of the earth can become very feeble, so that the least force suf- fices to disturb the stability of the equilibrium of the layers, which case can rarely happen during winter; third, the va- riation of temperature in a higher stratum of atmosphere always manifests itself by the relatively greater variations taking place between the lower layers. Kowalski's volume is, therefore, of interest to the meteoro- logical observer principally because of its bearing on the question of the temperature of the air. The important Experiments on Fog -signals, by Tyndall and others, under the auspices of the Elder Brethren of the Trinity House, have an important bearing upon meteorolog- ical matters, as they apparently give us a new method of ex- ploring the atmosphere ; in fact, as the spectroscope tells us of the total amount of moisture in a great length of the at- mosphere, so do TyndalPs aerial echoes tell us of irregulari- ties in density throughout a circle of many miles in diameter. Practically, however, the most important result of the Trin- ity House experiments has been to definitely establish the fact that two to four ounces of gun-cotton exploded 1000 feet above the sea by a rocket give forth such a volume of sound, and the sound-waves are so little affected by echoes or acoustic opacity, as to immensely surpass all other meth- ods of foo--sio-nalin hitherto tried. Such discharges were heard very loud at six miles, distinct, as distant thunder, at fifteen miles, and with a rumbling detonation at twenty-five miles. "A signal of great power, handiness, and economy is thus placed at the service of our mariners." 206 ANNUAL RECORD OF SCIENCE AND INDUSTRY. In the " Smithsonian Report " for 1877 is given a summary of the results of the investigations of Professor Henry in refer- ence to fog-signals and the audibility of sound, and as this summary includes Ins very latest results, it will have perma- nent interest. He finds the most efficient cause of the loss of audibility is the direct effect produced by the wind. Sound is heard farther when moving with the wind than when mov- ing against it. This is due to a change in its direction : it is refracted or thrown down towards the earth when mov- ing with the wind, but passes over the head of the observer when moving against the wind. Sometimes a strong upper wind opposite to the surface wind produces an apparent re- versal of the preceding law, as shown by his experiments in 1874. Although sound issuing from a trumpet or parabolic reflector is at first concentrated, yet it tends to spread so rapidly that at the distance of three or four miles it is heard nearly equally well on all sides. Neither fog, snow, hail, nor rain materially interferes with the transmission of sounds. Sound-shadows of great extent can be produced by build- ings or other obstacles. The alternate audibilitv and inau- dibility of a sound, as we approach to or recede from its origin, is attributed to the upward refraction of the sound- wave and its successive reflections at the upper and lower surfaces, or the riofht-hand and left-hand bounding surfaces of shallow or narrow currents of air. The phenomenon of an aerial echo which conies back to the observer from a portion of the horizon directly in front of the trumpet is attributed provisionally to the fact that in the natural spread of the waves of sound, some of the rays must take such a curved course as to strike the surface of the water in a perpendicu- lar direction, and thus be reflected back towards the orio-in of the sound. Pneumatics and Aeronautics. The ventilation of buildings and railway tunnels, etc., and the driving of the carriages in pneumatic tubes, railways, etc., introduce the application of principles and data that also have an application in meteorological problems; while, on the other hand, meteorological data relating to wind, tern- perature, and pressure enter into the computations of the engineers. Among these problems whose discussion we have noted during the past few years, we mention, the Ventilation PHYSICS OF THE GLOBE. 207 and Working of Railway Tunnels, by Morrison and others, in Proceedings of the Institute of Civil Engineers, art. xliv. ; also, in the same volume, the Pneumatic Transmission of Telegrams, art. xliii., by Culley, Sabine, etc. a very thor- ough and important discussion. The enthusiastic aeronaut De Fonvielle writes to Captain Iiowgate to say that the study of clouds and currents by means of small balloons will be now systematically pursued at the Paris Observatory. This is, he states, in consequence of the fact that Captain Howgate (at Mr. Abbe's suggestion) furnished the meteorologist of his preliminary expedition with a quantity of these balloons for use in the arctic re- gions. The resistance that the air experiences from friction and obstacles on the earth's surface is in many ways shown to be a very important factor in meteorology ; and as it is very difficult to make even an approximate allowance for this friction, it will conduce greatly to the reconciliation of theory with observation if some of the national meteorolog- ical systems will introduce the daily use of these balloons to determine the direction and velocity of the air-currents within 1000 feet of the earth's surface. Professor S. A. King, formerly of Boston, and now of Phil- adelphia, continues to make aeronautic ascensions as much as possible in the interest of the science of meteorology, although also strictly a business and professional matter. Could the results of his balloon voyages since 1851 be col- lected together, it would be seen that he ranks among the foremost aeronauts in his intelligent appreciation of the physical and meteorological problems that concern his pro- fession. Such a w T ork has, we understand, been in progress for some years, and doubtless now only awaits an enterpris- ing publisher. Professor Mendelieff is understood to be devoting his spare time to an extensive historical and scientific work on aeronautics. An important volume on aeronautics has been published by Tissandier, entitled " Histoire de mes Ascensions," being a record of twenty- four aerial voyages. The work gives special attention to the scientific exploration and study of the atmosphere, and is, of course, particularly valuable as containing Tissandier's own experiences. 208 ANNUAL RECORD OF SCIENCE AND INDUSTRY. The great event of the year in the application of aeronaut- ics to meteorology has been the success of Giffard's giant captive balloon. This balloon has proved, as far as is known, perfectly manageable, and has made from two to twenty as- censions on every pleasant day, carrying up each time about forty persons (among them always a meteorological observer). The revenue derived from it lias more than paid the orig- inal cost of the apparatus. A complete description of the balloon has been published by Tissandier, extracts from which have been published in numerous periodicals. The diameter of the inflated gas-bag is 36 meters; it was inflated with pure hydrogen made by the action of sulphuric acid on iron. The balloon is confined by a cable 660 meters long. The material of which the o-as-bao; is made has shown itself capable of retaining the hydrogen with scarcely any loss during four months. So complete has been Giffard's success that the Abbe F. Moigno, editor of Les JHondes, asserts that, had he been properly encouraged ten years ago by the French government, the investment of Paris could never have been completed, and the payment of five milliards need never have been forced upon France. The receipts during the first 60 days exceeded 8100,000, which was about the original cost of the balloon. In the beautiful weather of the commencement of October, the bal- loon accomplished between 8 A.M. and 6 P.M. 2-1 consecu- tive ascensions, so that in a single day 900 persons ascended and descended. The captive balloon is a veritable aerial sounding-line, and continually reveals the existence of super- imposed currents which escape the observer on the ground. One is frequently plunged, at an altitude of 100 or 200 me- ters, into rapid currents, while the air is calm below ; some- times, on the contrary, the balloon is becalmed while strong winds prevail at the earth. The Giftard balloon has been lately sold to a London company, and w