July 5, 1906] 



NA TURE 



vriiation and curious forms of a very interesting but 

 still much neglected group of insects. These figures 

 lia\c been drawn by Mr. Horace Knight in his usual 

 admirabl(i style. 



We have much pleasure in commending this volume 

 (in which a large number of new genera and species 

 are figured and described) to all entomologists who 

 are interested in exotic insects. W. F. K. 



OVU BOOK SHELF, 

 riniits and their Ways in South Africa. By Bertha 



.Stoneman. Pp. ix + 283. (London: Longmans, 



(ireen and Co., 1906.) Price t,s. 6d. 

 TilK schools in Cape Colony and in other South 

 .\frican colonies are already indebted to the publishers 

 of this volume for several useful educational books. 

 Although this book, and one on geology, are the only 

 lines issued under the title of the " .South African 

 Science Series," Messrs. Longmans have previously 

 published an elementary botany and a book on Soutli 

 African flowering plants. The present volume by 

 Miss Stoneman is written for younger children than 

 the two former. The treatment of the subject on an 

 elementary physiological and ecological basis is quite 

 the most suitable, and the author displays consider- 

 .ible originalitv, although at times she develops a 

 iruditv of expression. 



.\ chapter on seeds forms the introduction to the 

 phvsiological considerations of growth ; leaves and 

 their functions are then discussed, and four ecological 

 chapters precede the morphology of flowers, fruits, 

 and seeds. The latter half of the book is devoted to 

 il.issification, limited wisely to a description of the 

 principal orders, and the writer has drawn up tables 

 for differentiating all the genera mentioned; these 

 are exceedingly useful, but the key for distinguishing 

 tin- orders according to Bentham and Hooker's system, 

 and the synopsis based on Engler's arrangement, 

 would be more suitable for advanced students. 



One of the chief merits of the book lies in the 

 n.-itural manner in which rather diflTcult subjects, such 

 as the law of correlation of growth, are introduced; 

 also every opportunitv is taken to base instruction on 

 practical experiment. Certain mistakes or mis-state- 

 ments occur that might have been avoided with a 

 little more circumspection, and the mis-spellings are 

 more numerous than is consistent with careful read- 

 ing; but these defects are slight, whereas the author 

 has succeeded in giving plenty of character to the 

 book, and has written with the object of . stimulating 

 observation and inquiry on the part of the reader. 

 The book is well supplied with illustrations, of which 

 .1 fair proportion has been specially drawn or pre- 

 pared. 



Lectures on Compass Adjustment. By Captain W. R. 

 Martin. Pp. qS ; with three charts. (London: 

 George Philip and Son, Ltd., 1906.) Price 5.V. net. 

 In this book is reproduced a series of eight lectures 

 on compass adjustment in iron and steel ships, de- 

 livered at the Royal Naval College, Greenwich, to the 

 classes of senior officers as well as to navigating 

 officers up to the year 1902. There can be no ques- 

 tion that these lectures, profusely illustrated by 

 diagrams and supplemented by practical instruction 

 bv means of models, were in many ways of great 

 v.ilue to officers whose career was bound up with the 

 navigation of ships, where the compass might be 

 either a treacherous guide or a means of safety when 

 adjusted and cared for as the author describes. No 

 doubt the lecturer was able to answer questions asked 



NO. IQI4, VOL. 74I 



by his audience and to enlarge upon difficult points to 

 their mutual advantage, but now, when these aids 

 are absent and the student has to read lectures with 

 modified diagrams, it is incumbent on the author of 

 them to write clearly and with precision. 



Turning, however, to the text, it can hardly be said 

 that the author has succeeded in making his mean- 

 ing sufficiently clear in many places. Among the 

 more important of these the following require men- 

 tion : — " The magnetic force of the earth is of course 

 everywhere acting in only one direction " (the italics 

 are the author's), a very misleading assertion. The 

 expression " the line of dip is horizontal at the mag- 

 netic equator " is unsatisfactory. Again, what is the 

 student to understand from the words, " the compass, 

 may be regarded as a north seeking particle "? 



In lecture vi., following wrong premises, it is stated 

 that at a steering compass in H.M.S. Powerful the 

 coefficient \ = 0-790 would be increased to 0-968 after 

 correction by spheres. To obtain such an increase of 

 directive force has long been eagerly sought after in 

 vain, but, unfortunately, observation in the present 

 case shows that a value of about 0-830 is near the 

 truth after correction, .^gain, the results of observ- 

 ations made as described on p. 70 could not be used 

 in constructing chart No. i with any degree of 

 accuracy. With the large number of observations 

 from observatories and results obtained with absolute 

 instruments in the field, as well as relative observ- 

 ations at sea, there is no need to trust to inferior 

 results. 



The last lecture is devoted to the methods of adjust- 

 ing a compass with large errors, but it must be re- 

 marked that the directions given are not generally 

 agreeable with the practice of recent years. For ex- 

 ample, for all purposes connected with the heeling 

 error, the dip circle has long been discarded in favour 

 of the heeling-error instrument- 

 Finally, it will be observed that the equipment of 

 torpedo-lDoat destroyers and torpedo-boats with the 

 liquid compass is not referred tO- This is probably 

 an unintentional omission which may be reinedied in 

 future editions of this work. E. W. C. 



Lotus Blossoms. .\ Little Book on Buddhism. By 

 Maung Nee. Pp. vi+103. (Rangoon: Printed 

 Privately, igo6.) 

 .\ D.^iNTV ijooklet in which a number of passages from 

 various Buddhist writings have been gathered together 

 under different headings. As indicative of the high 

 tone and lofty character of the teaching in the 

 Buddhist writings, the following sentences may be 

 quoted : " Strive with all your strength, and let not 

 sloth find a place in your hearts." "The wise man 

 does not remain standing still where he has made a 

 beginning, but ever reaches forward towards fuller 

 enlightenment." " Idleness is a disgrace." These 

 are classed under the heading "correct aim," but 

 equally sound morality can be read in all the sections. 



Hydrographic Surveying. Methods, Tables, and 

 Forms of Notes. By S. H. Lea. Pp. 172. (New- 

 York : Engineering News Publishing Company ; 

 London : Archibald Constable and Co., Ltd., 1905.) 

 Price 8x. net. 

 This is an excellent volume, and thoroughly describes 

 the more complicated branch of hydrographical work, 

 such as rivers, lakes, &c. The book touches very 

 lightly on ocean surveying, and apparently is not in- 

 tended as a work on this subject. Several of the 

 terms used are not often met with in English works, 

 being .American technical terms ; but these soon be- 

 come familiar, and, as usual, are very descriptive and 

 to the point. H. C. Lockyer. 



