May 14, 1896] 



NATURE 



similar to those in Zoology already published. The series will 

 consist of twenty original photo-micrographs, accompanied by 

 descriptive letter-press and illustrations. The subjects included 

 in the part we have received comprise longitudinal and trans- 

 verse sections through the underground bud of Ei/tiiseliim, trans- 

 verse sections through leaf-buds of the Elm and the Ash, cuticle 

 of Arainaria, longitudinal section through node of Sycamore, 

 longitudinal .section through flower-bud of. Peony, tran.sverse 

 section through fruit of Date-palm, transverse sections through 

 flowertnuls of /ri's and Liliitin. 



Messrs. M..\LMn.LAN and Co. will shortly publi.sh "An 

 Intermediate Course of Practical Physics," by Prof. Arthur 

 Schuster, F.R.S., and Dr. C. H. Lees. The book will set 

 forth the cour.se of instruction in practical physics followed in 

 Owens College during the last five years. The explanations 

 having thus passed through the refining fire of a physical labora- 

 tory, have been cleared of all the obscurities which tease the 

 intelligence of the average student. The book was primarily 

 designed for use in preparing for the Intermediate B.Sc. and 

 First M.B. examinations of the Victoria University, but the 

 requirements of other Universities are so nearly identical that it 

 will appeal to a much wider circle of students. 



During the year 1895 '^^ Albany Museum, Grahamstown, 

 made excellent progress. From Dr. Schbnland's report we gather 

 that, owing to the large influx of specimens, the capacity of the 

 museum is overtaxed, and the erection of a new building has 

 become a matter of absolute necessity. The Government have 

 therefore been asked for a sum to devote to this purpose, and, 

 considering the value of the collections and the useful work the 

 museum is doing, and can still more effectually perform in a 

 suitable building, it is hoped that the grant desired will 

 be regarded as a judicious outlay. Owing to the rapid 

 growth and increasing value of the herbarium formed in 

 connection with the museum, the Committee think it de- 

 sirable that the expenses incurred by its management 

 should be borne by a fund apart from the general revenue 

 of the museum, and they have, therefore, asked the Government 

 to grant an annual sum of £,\<xi for this purpose. Dr. 

 Schonland has been experimenting with formaline as a substitute 

 for spirits of wine in preserving specimens. The results obtained 

 have been satisfactory, but he is afraid to discard spirits of wine 

 until he is sure that formic aldehyde is a perfectly stable com- 

 pound, and will keep for a considerable length of time in the hot 

 climate in which the museum is situated. 



The additions to the Zoological Society's Gardens during the 

 past week include a Rhesus Monkey {Macaais rhesus, 9 ), two 

 Sambur Deer (Census arislolelis, $ i ) from India, presented by 

 Mr. Greswolde-Williams ; a Brown Capuchin (Ccbiis fatiiellus) 

 from Brazil, presented by Mrs. J. Hicks ; three young Cheetahs 

 (Cynalurus juhatus) from Somaliland, presented by Mr. Kenneth 

 Foster ; two West Indian Agoutis {Dasyproila crisiala] from 

 the West Indies, presented by Mr. W. Wcldon Symington ; a 

 Chinese Goose {Anser cygnoidcs, i ) from China, presented by 

 Mr. L. G. Leverson ; a White-crested Cockatoo {Cacatita 

 crisiala) from Moluccas, presented by Mrs. Crofts ; two 

 Pennant's Parrakeets (Platyccrctis pennanti) from Australia, 

 presented by Mr. Clifford Brooks ; a Porose Crocodile (Croco- 

 dilus porosiis) from Java, presented by Mr. A. W. Richmond: 

 two Bennett's Wallabys (Halmaniriis beniietii) from Australia, a 

 Spotted Ichneumon (Herpesles uepalensi's), twrj Hamadryads 

 (Ophiophagiis claps) from India, deposited ; an Entellus Monkey 

 (Seinnopil/ieais entellus, 9 ) from India, a Great Anteater 

 {Myrmccophaga jubala), two Picui Doves (Colunibula picui) from 

 South America, two Blue-headed Pigeons {Starncenas (yaiw- 

 iephala) from Cuba, two Auriculated Doves (Zenaida a/iii- 

 NO. 1385, VOL. 54] 



culala) from Chili, four Cape Doves (^■Enas capensis) from South 

 Africa, two Crowned Pigeons (Goura coronata) from New- 

 Guinea, a Southern Fruit Pigeon ( Crocopus chlorogaster) from 

 India, a Nicobar Pigeon (Caltcnas nicobarica) from the Indian 

 Archipelago, purchased. 



OUR ASTRONOMICAL COLUMN. 

 Comet Swift, 1S96. — The following is Dr. Schorr's 

 ephemeris for Berlin midnight (Asl. jVacli., 3349). 



R.A. Decl. Bright- 



The path of the comet lies in the northern part of Cassiopeice 

 until May 25, when it passes into Cepheus. 



A Photographic Transit Circle. — Many attempts have 

 been made to replace the observer of star transits by a photo- 

 graphic plate ; but as most of them require the plate to register 

 star-trails, it is impossible in this way to record the fainter stars. 

 Dr. H. C. Russell has recently proposed another method, 

 which he believes will be capable of giving star positions with 

 much greater accuracy than is possible with the existing transit 

 circles, and is at the same time good for the fainter stars. The 

 instrument is virtually a photographic telescope of thirteen inches 

 aperture, mounted alongside a visual telescope in a rectangular 

 box, which turns on trunnions within a polar axis of the 

 " English " form. An electrically-controlled driving clock, and 

 circles for declination and right ascension complete the instru- 

 ment. On the scale suggested the circles may be large ones, so 

 that declinations may be read by microscopes to o"'i and right 

 ascensions to o-oi sec. The polar axis would be adjusted by 

 the familiar processes, and the instrument would be coUimated 

 like an ordinary transit circle ; the line of collimation of the 

 star camera must also be made parallel to that of the telescope. 

 The telescope would be set on the desired star before the 

 meridian, and the star would be constantly kept on the cross 

 wire while the plate was being exposed ; meanwhile the R.A. 

 would be read off by a second observer noting the times at 

 which the divisions of the circle pass a fixed microscope, the 

 relation of each division to the meridian being very accurately 

 determined. A third observer would read the declination circle. 

 The instrument would next be reversed in the polar axis, and 

 the observation repeated. If there were no collimation errors 

 or flexure due to the position of the telescope the photographic 

 images of the star would be superpcsed, and if they are not, 

 the point midway between the spots may be assumed to be the 

 mean of the unknown errors. There would of course be two 

 images of any stars, except the guide star, that might be in the 

 photographic field, and their positions relative to the guide star 

 would be determined by measurement of the photograph. The 

 advantages specially claimed are (i) the ob.servation does not 

 depend upon a flying shot at the bisection of a stellar image ; 



(2) at least a partial elimination of unknown errors is effected ; 



(3) the determination of R. A.'s with equal and extreme accuracy 

 for stars in all declinations: 



Mr. Tebbutt's Observatory. — The report for 1895, which 

 we have just received from Mr. Tebbutt, of Windsor, N.S.W., 

 is a splendid illustration of what can be accomplished almost 

 single-handed by an enthusiastic astronomer. Not less than 

 957 transits of stars were observed during the year, and this in 

 addition to a varied series of other observations. A large number 

 of occultations of stars was observed, and what may be regarded 

 as a feat in this class of work was accomplished on August 29, 

 when both phases of the occultation of the fifth magnitude star 

 B.A.C. 6127 were observed in full sunlight. The micrometric 

 work includes numerous measures of the positions of the minor 

 planets Hebe and Ceres, and of seventeen double stars which 

 are of peculiar interest. Jupiter's satellites and certain variable 

 stars also received attention, and the various meteorological 

 phenomena were recorded. Eleven papers on the results of the 

 astronomical work were published during the year. 



