112 



KNOWLEDGE. 



[May. 1901. 



BOOKS RECEIVED. 



The Birds of Siberia. By the late Henry Seebohra. (Miu-rav.) 

 Illustrated. 12s. net. 



The Romance of the Heaceiu. By Prof. A. W. Bickerton. (Swan 

 Sonnensehein.) Illustrated. 5s. 



Arsenic. By Prof. J. Alfred Wanklvn, m.e.c s. (Kegan Paul.) 

 23. fid. 



The Design and Construction of Oil Engines. By A. H. 

 Goldingham, \r.B. (Spon.) Illustrated. 6s. net. 



The Elements of Darwini.'sm. By A. .1. Ogilvy. (Jarrold.) 23. 6d. 



The Colour Cure. By A. Osborne Kaves. (Wellby.) Is. 6d. net. 



Twentieth Century Inventions: A Forecast. By George Suther- 

 land, 5I.A. (Longmans.) 4s. 6d. net. 



Elementary Practical Mathematics. By M. T Ormsby. (Spon.) 

 Illustrated. 7s 6d. net. 



Disease in Plants. By H. Marshall Ward, sc.D., F.B.s. 

 (Maemillan. ) 7s. 6d. 



A Te.rt-Book of Sciographii. By John H. A. M'lntyre. II.I.M.E. 

 (Blaekie.) Illustrated. Ss. 6d. 



The Elements of Differential anil Integral Calculus. By J. AV A, 

 Young and C. E. Linebarger. (Ilirschfeld Bros.) lOs. 6d. net. 



The Structure and Inherent Motions of the Universe. By Edward 

 Meyer. (Adelaide : A. & E. Lewis.) 



Familiar Wild Birds. Part I. By AV. Swaysland. Illustrated 

 by A. Tliorburn and others. (Cassell.) 6d. 



The Photo-Miniature. Vol. II., Xo. 2i , March. 19U1. (Dawbarn 

 .ind Ward.) 6d. 



Stonghurst College Observatory . Results of Meteorological and 

 Magnetical Observations. (Clitheroe : Parkinson and Blacow.) 



Whist Dialogues. By Major .Tack Tenace. (Bruielles: E. Wage- 

 mans. ) 



A Natural Sustem of Map Drawing. By Prof. A. W. Bickerton. 

 (Swan Sonneaschein.) 



The Scientifc Soil: Bacteria. By Alexander Bamsay. (R. L. 

 Sharlaud. ) Is. 



A La Conqufte du del ' F. C. de Xascius. (Vantes : A. Dugas.) 



Tlie Use and Abuse of the Harrogate Mineral Waiters. By Arthur 

 Roberts, 51. D., M.E c.s. (Harrogate : Robert Ackrill.) 6d. 



Archives of the Roentgen Ray. August, 1900, and .Januiiy, 1901. 

 (Kebman. Lid.) 43. net. 



Astronomical. — An account of a new astronomical 

 undertaking of great magnitude has recently been given 

 by Professor Auwers. The object is nothing less than to 

 collect into one great catalogue the determinations of the 

 positions of stars which have been made during the last 

 one hundred and fifty years, and to reduce them all to the 

 equinox of 187.5. At the present time the observations 

 are distributed through more than three hundred 

 catalogues, and much time is lost in consulting these 

 different sources of information and in correcting the 

 positions for the epoch required. It is estimated that the 

 total number of star places to be dealt with will be about 

 a million, and proper motions will be iuvesti.'ated when- 

 ever possible. The work is to be undertaken by the Berlin 

 Academy of Sciences, which received a permanent endow- 

 ment for it during the bicentenary celebrations last year. 

 Dr. F. Ristenpart has been appointed cliief of the com- 

 ])Uting staff, and the work will be under the general 

 superintendence of a committee of which Professor 

 Auwers is president. 



The piesence of free hydrogen as a normal constituent 

 of our atmosphere to the extent of about two volumes in 

 ten thousand, has been demonstrated by the experiments 

 of M. Armand Gautier. The result is of great interest iu 

 connection with Dr. Johnstone Stoney's views as to the 



tendency of gases to escape from the atmospheres of 

 planets when their molecular velocities are great enough 

 to overcome the gravitational attraction. On this view 

 the earth cannot retain hydrogen, but there is of course a 

 possibility of its continued production. Professors Liveing 

 and Dewar, who have previously found free hydrogen in 

 air, suggested that there might be a continued accession 

 of hydrogen from interplanetary space. 



A suggestion made by Lord Eayleigh in 1893 to the effect 

 that in astronomical photograjihy the plates should be 

 accommodated to the telescopes rather than telescopes tothe 

 plates, has recently been acted upon with complete success 

 at the Yerkes Observatory. Photographs taken with the 

 great refractor (which is con-ected only for the visual rays) 

 on isochromatic plates, through a suitably-coloured screen, 

 are perfectly defined, and the large scale greatly augments 

 their value for purposes of measurement. Pictures of the 

 stai- cluster in Hercules and of portions of the moon's 

 surface show a great amount of detail. — A. F. 



Botanical. — The force exerted by swelling .seeds has 

 been demonstrated by experiments made by Dr. D. T. 

 MacDougal, who has published the results obtained in 

 the March number of the Journal of the Nev York 

 Botanical Garden. It was ascertained by means of a 

 manometer that peas, on being wetted, exerted a pressure 

 sufficient to compress a column of air from a length of 

 6i5li to 78 inches, which is equal to eight atmospheres, or 

 120 pounds to the square inch. 



Herr von Mindeu has a paper in the last published 

 part of Flora on the irritability of the style in two species 

 of Arctotis (A. aspera and A. calendulacea), which recalls 

 that exhibited by the column in species of Stylidium, and 

 which is doubtless concerned in the function of pollination. 

 It was observed that the style on being touched by a 

 needle, or the body of an insect, immediately became 

 strongly concave on the side touched, so that the stigmas, 

 which had received a coating of pollen on the outside 

 during their passage through the staminal tube, would 

 come in contact with the irritating agent, to which, in the 

 case of an insect, some pollen would be conveyed. 



In Hooker's Icones Plantarum, Vol. xxvii.. Part 4, Mr. 

 Hemsley continues his revision of the genus Sajiiiim, 

 to which belongs the tree that produces the Colombian 

 india-rubber of commerce. Eight species are described, 

 five of them being new. The Peruvian Castilloa australis 

 is described and figured in the same work. This plant 

 yields caoutchouc, like the well-known C. elastica, the 

 chief source of Central American india-rubber. 



Da< Pflan-.eiireich is the title of a colossal work which 

 is now being published under the editorship of Dr. 

 Engler, of Berlin. The three parts already issued 

 consist of monogi'aphs of the Musaceje, Typhaeeae, 

 Sparganiacese, and Pandanacese. The plan of the work, 

 which, it is anticipated, will take twent)- years to com- 

 plete, is somewhat the same as that followed in Engler & 

 Prantl's Pflan.enfumUien. but in Dan Pflanzenreich 

 species, subspecies, and varieties are described as 

 well as orders and genera. The concise descriptions are 

 supplemented by illustrations of the more characteristic 

 species. — S. A. S. 



Meteorological. — In the present state of knowledge 

 and opinion, the new meteorological journal, Climat,* 

 strikes one as rather a bold venture. It explains weather 



* Published in St. Petersburg. Nersky, 88, in fo ir languages. 

 Twice a month. Agents for British Isles : Hugh Rees, Limite'^, 

 121. Fall Mall, London, S.W. 16s. per annum. 



