January 20, 1898] 



NATURE 



267 



interest in the community. Surely one of the objects, 

 if not the main object of such a book as this, is to 

 promote the cultivation of the science among an in- 

 structed, but not specially instructed, public. For whom 

 else is the book written ? It is not a work of reference 

 intended to be used by the astronomer ; it is not suffi- 

 ciently full. The earnest student of astronomy is catered 

 for by treatises of a more serious character. In point of 

 fact the book occupies, to some extent, the ground which 

 Sir Robert Ball has so well covered, and appeals 

 generally to the same class of readers. 



Another disadvantage springs from this slight, and 

 Miss Gierke must pardon us if we say, unworthy, sketch 

 of spectroscopic advance. Justice is not accorded to 

 those who have worked strenuously and successfully as 

 pioneers in this branch of science. One unacquainted with 

 the history of the science might suppose that our know- 

 ledge of it began and ended with the work of Sir William 

 Huggins. We do not mean to imply that there is one 

 word here that is not justified by his great reputation, but 

 only to regret that the names of other equally earnest and 

 equally capable workers 'are suppressed. We think the 

 omission of all reference to the work of other physicists, 

 both at home and abroad, makes the survey of the general 

 progress of the science too incomplete, and might indeed 

 be likened to the representation of Hamlet with the omis- 

 sion of the Prince of Denmark. No doubt the prominence 

 given to some astronomers, and the silence maintained 

 with regard to others, are accidental ; but it unfortunately 

 suggests that the author's mind is warped in special 

 directions, preventing a wholly unprejudiced survey being 

 taken, and suggesting a biassed arrangement of the facts. 

 Happily, in such an elementary work, when we come 

 .to greater detail, points still open to controversy and 

 further elucidation do not come before us. We have 

 only to deal with admitted and recognised truths, and 

 here Miss Gierke is a safe guide. The section describing 

 the solar system leaves little to be desired ; few could 

 probably have arranged an equal number of facts in the 

 same space without becoming dull and wearisome. By the 

 admirable illustrations supplied, we are in some instances 

 enabled to see the planets and the details of their surface 

 markings as they are revealed in the most powerful tele- 

 scopes, while the latest views and speculations of the 

 observers are recorded with ample fulness. We antici- 

 pate that on this section the general reader will dwell 

 with the greatest interest and delight. 



Mr. Fowler's work, without much reason, is sand- 

 wiched in between the preliminary historical chapter 

 and this description of the solar system. It is termed 

 geometrical astronomy, not a very happy title, but 

 spherical was, no doubt, felt to be too ambitious 

 a description, and it certainly does deal with many 

 of the problems that belong to the earth's figure 

 and motions. Trigonometrical expressions are prac- 

 tically excluded, but by the aid of diagrams a good 

 many simple problems are very satisfactorily explained. 

 The description of instruments is an interesting feature 

 in this section, and is written with that simplicity and 

 clearness which characterises all Mr. Fowler's work when 

 dealing with mechanical operations. 



Mr. Gore furnishes the last part of this trilogy. His 

 domain is the sidereal heavens, and, considering the 



NO. 1473- VOL. 57] 



space at his disposal, his work is very thoroughly done. 

 We could have wished, and so possibly did Mr. Gore, 

 that he had been allowed to use Greek letters to 

 designate the stars in their lespective constellations. An 

 uncomfortable strange appearance is given to many old 

 friends dressed up in this unfamil iar fashion. But when 

 one gets over this peculiarity it will be found that the 

 facts connected with binary systems, with temporary and 

 variable stars, with the motion of the sun are clearly and 

 accurately stated, and give a very complete idea of the 

 present condition of our knowledge of the sidereal 

 heavens. 



A few very obvious errors are occasionally met with in 

 the course of the book ; but where so much has been read 

 with pleasure, it seems a very ungracious task to place 

 the finger on these few blots, which, no doubt, will dis- 

 appear in subsequent editions. If any one prides him- 

 self on his accuracy, let him write an elementary text- 

 book on a subject in which the facts are continually 

 accumulating, and the deductions from them being 

 constantly modified, and he will probably find that his 

 self-complacency is scarcely warranted. W. E. P. 



OUR BOOK SHELF. 



Manuel (P analyse chimiqiie appliquee a fexamen des 

 prodiiits indiistriels et commerciaux. By Emile 

 Fleurent. Pp. iii -V 582. (Pans : G. Carre et G. 

 Naud, 1898.J 

 The author states in his preface that he has written 

 with a threefold aim, namely : (i) to give general methods 

 of qualitative and quantitative mineral analysis and 

 organic analysis of an elementary character, free from all 

 details not absolutely useful ; (2) to avoid methods of 

 work that are too long for those who are pressed for time 

 or who have not sufficient general knowledge, giving in 

 each case only one method (or occasionally two) that 

 leads quickly and surely to the desired result ; and (3) 

 to bring together in one volume the methods of exam- 

 ination of the more import ajit., though the most diverse of 

 the products which one meets with in the laboratory of 

 the industrial chemist. Accordingly we find in some 556 

 pages of clearly printed and well-spaced matter some 

 preliminary observations with reference to apparatus, a 

 section on qualitative analysis, and methods for the 

 quantitative examination of the commoner metals and 

 minerals containing them, besides, among other things, 

 water, inorganic pigments, cements, &c., compounds of 

 the alkalis, manures of various kinds, soils, animal and 

 vegetable products, such as cellulose, tannin, milk, fruits, 

 fermented liquors, wines, and textile fabrics, the estimation 

 of acetone in methylated spirit, and the determination of 

 the flashing point of petroleum, &c. It is obvious that 

 where so much ground is covered in so comparatively 

 small a space, that in some cases at least there cannot be 

 room for more than a mere summary of the details of 

 the method given. It is generally a matter of opinion as 

 to which is the best of several alternative methods, and 

 often, too, a slight variation in the sample from what is 

 most usual, renders a variation in the process desirable. 

 It must have been a very difficult task to select the one 

 or two methods in each case ; but, taken as a whole, they 

 are fairly representative. If the space devoted to the 

 figures of beakers and other apparatus, and to the exceed- 

 ingly meagre description of the qualitative reactions of 

 the common acids and bases had been devoted to an 

 expansion of the other part of the book, the usefulness 

 of the volume would have been much increased. We 

 doubt, for example, the need for telling any one who con- 

 cerns himself with such work as is here described, that 



