60 



KNOWLEDGE 



[March 1, 1899. 



selves of the opportunity of securing its friendly guidance and 

 help in their laudable aims. 



The Last Link. By Ernest Haeckel. (Black.) 2s. 6d. 

 Prof. Haeckel here goes over, critically, the evidence and the 

 different conclusions which at present represent our scientific 

 knowledge of the descent of man and of the various stages of 

 '• his animal pedigree." The book is a reprint of his address in 

 August last at the Fourth International Congress of Zoology at 

 Cambridge. A series of biographical sketches of Lamarck, 

 Saint-Hilaire, Cuvier, Baer, Mueller, Tirchow, Cope, Koelliker, 

 Gegenbaur, and Haeckel. is added by Dr. Hans Gadow, as well 

 as chapters on "Theory of Cells," "Factors of Evolution," 

 " Geological Time," and so on. As we have long since learned to 

 expect, there is no " beating about the bush " in Prof. Haeckel's 

 manner — only one construction can be put upon his words. 

 Evolution, as taught by Darwin, is his watchword. " Whence 

 our race has come ; what are the limits of our power over 

 Nature, and of Nature's power over us ; to what goal are we 

 tending — these are the problems which present themselves anew 

 and with undiminished interest to every man born into the 

 world.'' On these matters the professor exercises his powerful 

 reasoning faculties, and the result is full of interest, whether we 

 are at one with him or not. 



The Structure and CJussificiition of Birch. By Frank E. 

 Beddard, m.a., f.R.s. (Longmans.) Illustrated. Mr. Beddard's 

 papers on the structure of birds are well known to those 

 who attend the meetings, or read the Proceedings, of the 

 Zoological Society. In "this book Mr. Beddard has brought 

 together the results of the researches into the anatomy of 

 birds undertaken by himself and his two predecessors. Prof. 

 Garrad and Mr. W. A. Forbes, in the office of Prosector to the 

 Zoological Society. Some one hundred and fifty pages of the 

 book are devoted to a general sketch of bird structure, in which 

 the author has avoided " histological detail, and the elaborate 

 description of anatomical facts, which are not, in the present 

 state of our knowledge, of great use in classification." The 

 main portion of the book consists of detailed accounts of the 

 structure of different groups of birds. The author has a wide 

 knowledge of his subject, and expresses himself with clearness 

 and directness. The book contains a multitude of facts, 

 elucidated in many cases by excellent illustrations. It should 

 prove of great service to those who are working at the anatomy 

 of birds, as well as to those who wish to use it merely as a work 

 of reference. 



It is refreshing to see such a well arranged, neatly printed, 

 and tastefully illustrated catalogue of chemical, metallurgical, 

 bacteriological apparatus, and pure chemicals, as that just issued 

 by Messrs. Becker & Co. It has a very complete index, contains 

 nearly seven hundred pages and three thousand five hundred 

 illustrations. A pleasing feature is that the figures in nearly 

 every case are placed op])osite the number and the matter 

 describing them. The catalogue includes many new pieces of 

 apparatus which we have not previously seen in publications of 

 this kind. The volume is well bound and has a very attractive 

 appearance. 



The Heavens at a Glance, a handy card calendar for 1899, 



by Mr. Arthur Mee, f.r.a.s., is this year printed in type, and in 



several other points is a great improvement on previous issues. 



We have received from Mr. Wm. Harbutt, of Bath, a .'sample of 



Ilia new modelling material, " Plasticine." 



BOOKS RECEIVED. 



Volcanoes. By Prof. T. G. Bouney, d.sc, f.b.s. (Murray.) 

 Illustrated. 6s. 



The Science of Life. By J. Arthur Thomson. (Blackie.) 28. 6d. 



Practical Zoology. By A. Milnes Marshall and C. Herbert Hurst. 

 Fifth Edition. (Smith, Elder & Co.) Hlustrated. 



Landmarlcs in English Industrial Bistory. By George Townsend 

 Warner. (Blackie.) os. 



Birds. By A. H. Evans, M.A. The Cambridge Natural History. 

 (Macmillan.) Illustrated. 178. net. 



West African Travels. By Mary H. Kingsley. (MacmiUan.) 

 Illustrated. 2l3. net. 



In the Australian Bush. By Eiohard Semon. (Macmillan.) 

 Illustrated. 21s. 



Outlines of Industrial Chemistry. By Frank Hall Thorp, PH.D. 

 (Macmillan.) Illustrated. 15s. net. 



A Setrospect of Eight Decades. By Kev. Edward L. Berthon. 

 (Bell.) 5s. net. 



The Sound of a Voice that is Still. By Archie Campbell. 

 (Eedway.) 5s. net. 



Wonders of the Bird World. By B. Bowdler Sharpe. (Wells, 

 Gardner, Barton & Co.) Illustrated. 6s. 



The Story of the Mind. By J. M. Baldwin. (Newnes.) Illus- 

 trated. Is. 



Kant on Education, Translated by Annette Chiirton. (Kegan 

 Paul.) 2s. 6d. net. 



A Course of Wood-Carving according to the Japanese Method. 

 By Charles Holme. (Offices of the Studio.) Illustrated. 



Whitaker's Naval and Military Directory, 1899. 5s. 



Siddhdnta-Darpana—a Treatise on Astronomy from the Chinese. 

 Edited by Joges Chandra Bay, M.A. (Indian Bepository : Calcutta.) 

 Three Bupees. 



Remarkahle Comets. By W. T. Lynn. (Stanford.) 6d. 



Calendar and History of the Science and Art Department. (Eyre 

 & Spottiswoode.) Is. 8d. 



La NouveUe Monadologie. Par Ch. Renouvier et Louis Pratt. 

 (Armand Colin et Cie : Paris.) 12 fr. Vol. XYI. 



The Auk : a Quarterly Journal of Ornithology. Vol. XVI. 

 No. 1, Jan. (Foster : New York.) Illustrated. 75 cents. 



Di/namics. By Wm. Briggs and G. H. Bryan. (Clive.) 3s. 6d. 



Practical Work in Physics. By W. G. Woollcombe. (Clarendon 

 Press.) Illustrated. 2s. 



A Short Way out of Materiali.tm . By Hubert Handley. (Riving- 

 tons.) Is. net. 



Archives of the Rontgen Ray. November, 1898. (Rebman Pub- 

 hshing Co.) 



♦ 



SUNSET ON THE MARE CRISIUM. 



By E. Walter Maunder, f.r.a.s. 



THE principal object in the accompanying plate is 

 the Mare Crisium ; one of the best studied of all 

 of the lunar " grey plains." It is the most sharply 

 defined and completely outlined of its class, and, 

 so far as we can judge, it is the deepest, deeper 

 even than the Mare Serenitatis, which lies in the same 

 quadrant, and which it resembles in that the enclosed plain 

 is divided into two regions at different levels ; a broad 

 marginal zone surrounding a central area which lies con- 

 siderably lower. The frequency with which it has been 

 observed is, no doubt, partly due to its being visible during 

 the first half of the month. It will be noted that at the 

 time when the photograph was taken the sunlight was 

 already leaving the Mare, although the moon was but two 

 and a half days past the full. It is thus an object for study 

 in the evening hours, not the morning. If we add to this its 

 small dimensions among the Maria, rendering it an object 

 that may be easily studied as a whole, and its complete 

 separation from other regions of its class — for it stands 

 amongst lunar " Seas '' as the Caspian amongst the waters 

 of our own world — its attractiveness to selenographers is 

 sufficiently explained. 



Its very separateness, however, places the Sea of Crises 

 in a somewhat different category to the Maria generally. 

 The evidences, which are so abundant elsewhere of the 

 destruction of ring-plains and crater-plains, by the material 

 which forms the floor of the Mare, are scarcely to be noted 

 here. On the other hand, though strongly resembling not a 

 little in some of its characteristics the great walled plains 

 like Clavius and Schickhardt, its far greater area forbids its 

 being ranked with them, since even Clavius is but one- 

 fifth the size. 



Near the opposite limb of the moon, and practically on 

 the same diameter, is another small Mare, smaller than 

 the Crisium, and almost as completely isolated. These two 

 " Seas " form the ends of a great arch composed of the 

 greater Maria, which seem to follow one another like beads 

 strung on a thread. It has often been pointed out that 

 this arrangement seems to indicate that at one time they 

 marked out the lunar equator, for they lie nearly on a 



