May 30, 1895] 



NA TURE 



1 1 



melrical progression, and that the cessation of their growth is 

 causetl by the diminution of their food supply. 



Mr. H. (;. Wklls's scientific fantasy, the " Time Machine," 

 M-hicti lias l)cen appearing as a serial in the New Rcfieiu, will be 

 Hublished in volume form, by Messrs. Heinemanii, in the course 

 of a few days. 



Mr. GlsBERT KAl-J-has arrangcil with Messrs. Whittaker and 

 Co. for a translation from the tierman of his new work on the 

 " Alternate Current Transformer." The volume will be published 

 in the " Specialists' Series " in the autumn. 



TiiK papers on the relation of diseases of the spinal cord to 

 the clistriliution and lesions of the spinal blood-vessels, recently 

 contributed by Dr. R. T. Williamson to the Medical Chronicle, 

 have been reprinted and puljlished in book form by Mr. 

 H. K. Lewis. 



This week's new editions include Prof. T. E'reston's philo- 

 sophical " Theory of Light,'" published by Messrs. Macmillan. 

 More than one hundred pages of new matter have bev.n added, a 

 v,aluablc addition being an account of Prof. Newcomb's experi- 

 ments to determine the velocity of light. The second edition 

 has apiwared of the late Prof Cayley's " Elementary Treatise 

 on Elliptic Functions" (Macmillan), the first edition of which 

 was published in 1876. Another second edition, received during 

 the pa.st week, is "A First Book of Electricity and Magnetism," 

 by Mr. W. Perren Maycock. This book, now greatly enlarged, 

 is published by Messrs. Whittaker and Co. 



The Deutsche Seewarte, which, with the year 1894, has com- 

 pleted its twentieth year of useful activity, has just issued the 

 seventeenth volume o( .-Iits dent Archill This work, which has 

 contained many elaborate and valuable discussions in nieteoro- 



(*gy, navigation, and nautical astronomy, is now devoted more 

 especially to discussions of practical utility to seamen. Among 

 •he articles of more general scientific interest may be mentioned 

 one by Dr. Grosimann, on the application of Bessel's formula 



n meteorology, and one by Dr. Maurer, on the application of 

 graphical methods in meteorology and physics generally ; the 

 latter investigation may possibly le.ad to the substitution of this 

 method for the use of tables in some of the problems of nautical 

 astronomy. 



The additions to the Zoological Society's Gardens during the 

 past week include si.\ Hairy-footed Jerboas {Dipiis kirtipes), 

 two Lesser Egyptian Gerbilles (GerbillHS •e^yptiiis), two Lybian 

 Zorillas (hlonyx lyhica), two Grey Monitors ( I'aranus griseiis), 

 two Egyptian Mastigures (Uromaslix spinipes), three Egyptian 

 Geckos (Tareiilola aitnii/aiis), a Common Chameleon 

 (Chaimeleon vulgaris), seven Common Skinks (Sciitciis 

 officinalis), two Cerastes Vipers (I'ipera cerastes), two 

 Diademed .Snakes [Zamenis diadema), from Egypt, presented 

 l)y Dr. John Anderson, F.R.S. ; a Grysbok (Neolragiis 

 melanotis, 9 ), from South Africa, presented by Mr. J. E. 

 Matcham ; a Wapiti Deer {Cerriis caiiaJensis, 9 ), a Japanese 

 Deer (Cenms siia, 9 ), a Burchell's Zebra {Ei/uiis biirchelli, i ), 

 two Polar Hares (Lepus glacialis), born in the Gardens. 



OUR ASTRONOMICAL COLUMN. 

 Mkrcukv and VENti.s.-The planet Mercury is now an 

 evening stiu, and will be favourably placed for observation until 

 towards the end of June. The greatest elongation will occur on 

 June 4 at i jli., when the planet will transit about ih. 42m. after 

 the >un ; the declination will then be nearly 25' north, and the 

 apixirent diameter a little over 8". Jupiter will lie in close 

 proximity to Mercury during the present period of its visibility, 

 •"o that observers not employing telescopes must be careful to 

 di.scriminale between the two ; at the elongation. Mercury will 

 precede Jupiter by about 8m. in R..\., and will be about I.J 



NO. 1335, VOL. 52] 



degrees farther north. The two planets will be in actual con- 

 junction on June 8 at 4h., Mercury being 0° 47' N. of Jupiter. 



\'enus, also, is most fax'ourably situated for observation at 

 the present time, and the great brilliance of the planet in the 

 western sky after sunset cannot fail to attract the attention of 

 the most indifterent. It will not, however, reach maximum 

 brightness until .\ugust 13. The greatest eastern elongation 

 will occur on Jul)' II, and the apparent diameter will increase 

 from 16' on June i to 59' at the inferior conjunction on Sep- 

 tember 18. 



The Total Solar Eclipse of 1S98 January 21-22. — In 

 addition to the eclipse of the sun" which will take place on 

 August 8, 1S96, and for which we understand preparations are 

 already well in hand, there will be another important solar 

 eclipse before the end of the present century. This will occur 

 on January 21-22, 1898, and the Nautical Almanac Circular, 

 No. 16, gives local particulars of the same for that portion of 

 the path of the shadow which lies across India. At Rajapurthe 

 duration will be 2m. I '93. and the altitude of the sun 53° ; at 

 Xagpur, im. 177s. with an altitude of 46°; and at a position 

 south of Benares, im. 43'6s. with an altitude of 40'. Informa- 

 tion as to the meteorological conditions prevailing at various 

 points along the track of the eclipse during the latter part of 

 January is being collected through the assistance of Mr. Eliot, 

 .Meteorological Reporter to the Government of India. It is 

 proposed to publish this information early in 1897. 



As the next sun-spot minimum is not due until the year 1900, 

 observations of the phenomena of this eclipse will furnish in- 

 formation as to the solar conditions during the transition from 

 maximum to minimvmi. 



The AsTRO-i'HOTOGRArHic Chart. — The third part of the 

 second volume of the Bulletin of the International Permanent 

 Committee, gives an account of the present state of the great ■' 

 undertaking to prejiare a photographic catalogue and chart of th^ 

 heavens. The reports from the various participating observatories 

 indicate in general a rapid advance towards the completion of the 

 photographs which are intended to form the basis of the cata- 

 logue ; four of the eighteen observatories have already completed 

 the zones allotted to them, and it is expected that at least eight 

 more will reach this stage by next spring. Systematic work at 

 the South American observatories has been seriously interfered 

 with by [political events ; but it is satisfactory to learn that the 

 Australian and Cape of Good Hope astronomers are pre])ared to 

 come to their assistance. .An immense number of catalogue 

 plates with short exposures has been taken with the various 

 instruments, no less than 753 having been taken at Paris, and 

 1562 at the Cape. The measurement of the catalogue plates is 

 also in a forward state at several of the observatories, but the 

 reductions have scarcely been commenced. 



For the chart itself, not one-third of the requisite photographs 

 have yet been obtained, but the progress of this part of the work 

 is necessarily slow, in consequence of the long exposures 

 required. 



l)r. Gill |)roposes that the Committee should meet in 1896, to 

 reconsider the. various questions left oi>en at the former con- 

 ference, among which one of the most important relates to the 

 scale of magnitudes to be atlopted. 



Four iniiiortant memoirs also form part of the present report. 

 Prof. Turner and M. Prosper Henry discuss iiifl'erent methods 

 of reducing the plates, M. Trepied gives his experience and 

 views as to the determination of m.agnitudes. and M. Donner 

 discusses the various corrections for instrumental errors. 



Award or the Watson Medal. — On the recommendation 

 of the Board of Trustees of the Watson Fund, the U.S. 

 National Academy of Sciences last year unanimously awarded 

 the Watson medal to Dr. S. C. Chandler, for his investigations 

 relative to variable stars, his work in connection with the 

 variation of terrestrial latitudes, and his researches on the laws 

 of that variation. The recommendation was noted in these 

 colunms a year ago, and a description of the founding of the 

 award was given (Nature, vol. 1. p. 157). The medal was 

 presented to Dr. Chandler at the recent meeting of the National 

 .\cademy, and Science for May 3 contains the report of the 

 Trustees, setting forth the grounds upon which the awai.d was 

 made, and briefly stating the history of the investigation ol 

 changes of latitude. Dr. Chandler's work upon the subject 

 began with observations made by him in 1884-85. His observ- 

 ations, continued uninterruptedly for thirteen months, revealed 

 a progressive change of a pronounced periodical character in the 



