1899] SCIENCE FOR THE YOUNG 471 



style and a less indigestible manner. The various sections have been revised 

 by specialists — all Dublin men — whose labours are gratefully acknowledged ; 

 and the claim of the editor that the young reader will not have much to 

 unlearn is fully justified. The style is fluent, yet not diffuse ; the facts are 

 well selected and well expounded. The zoology is particularly interesting, and 

 contains a new parrot story of distinct merit. The figures are poor, shaded, 

 yet without the least perception of tone-relation, like those of a century ago. 

 Yet they are not without some spirit : the leary lemur, the supercilious tapir, 

 and the 'orty proud gazelle, will be attractive to children ; but the tusks of the 

 hippopotamus are drawn outside the upper lip ; the lion (passant) has a true 

 heraldic air ; and the " baboon," which will suggest a toy-shop poodle to the 

 child, recalls to ourselves the illustrations to the old editions of Marco Polo or 

 Sir John Maundeville. Again, of the three very bad figures of vegetable 

 histology, that called "woody tissue" is easily worst, and a gratuitously useless 

 disfigurement to the beautifully printed text. The paper is unduly thick, and 

 the physical weight of the book (1 lb. 5 oz.) excessive; while the sheets are 

 so carelessly stitched that it opens badly and will soon fall to pieces, just 

 because of the merits of the letterpress. M. 



THE SECRET OF LIFE. 



Die Kontinuitat der Atomverkettung, ein Strukturprinzip der lebendigen 

 Substanz. By Dr. Georg Hormann. 8vo, pp. 118, with 32 figures. 

 Jena: Gustav Fischer, 1899. Price 3 marks. 



The aim of this pamphlet is defined by the author to be the application of 

 Pfliiger's hypothesis of the chemical continuity of protoplasm to various biological 

 problems, with the view of showing that it renders these more readily compre- 

 hensible than any other hypothesis. Pfliiger emphasised the power of poly- 

 merisation displayed by many organic substances, and suggested that in the 

 living organism this might go on indefinitely so that great masses might arise, 

 and the whole nervous system, for example, might be built up of a single giant 

 molecule. Accepting this suggestion in its entirety, the author seeks in' a series 

 of chapters to show that it renders explicable such phenomena as the propaga- 

 tion of stimuli along a nerve, the effect of nerve section, the action of electrical 

 organs, and so on. The pamphlet is illustrated by numerous ingenious and com- 

 plicated diagrams, and may be recommended to those persons to whom such 

 phrases as the " principle of chemical continuity " appeal strongly ; to others 

 we fear much of it will seem vanity and vexation of spirit. As in so many 

 similar cases it is difficult to find out whether the author regards the hypothesis 

 as merely of value in the construction of mental pictures of the more compli- 

 cated phenomena of life, or whether he seeks to explain these phenomena in 

 terms of chemistry and physics. We have noted what seems an excessive 

 number of misprints, and cannot congratulate the author upon his style, which 

 is not calculated to assist in the comprehension of a difficult subject. N. 



HISTORY OF ASTRONOMY. 



A Short History of Astronomy. By Arthur Berry, M.A. 8vo, pp. 

 xxxii. + 440, with 105 illustrations and nine portraits. (University 

 Extension Manuals, edited by Professor Knight.) London: John 

 Murray, 1898. Price 6s. 



Unlike several books which have appeared within the last few years, in 

 which the principal events of the history of astronomy have been described in 

 the form of biographical sketches, the present work seeks to present the reader 

 with a complete account of the historical development of astronomy without 

 giving undue prominence to the biographical element. It is evident that Mr. 

 Berry has most carefully prepared himself for his task not only by reading the 



