200 



NATURE 



[April 14, 192 1 



tory, and the Imperial Institute. That the work is 

 up to date is shown by the inclusion of the Insti- 

 tute of Physics, which was incorporated during 

 the past year. We have so far noted one omis- 

 sion only — the Imperial Mineral Resources 

 Bureau. 



The World of Sound: Six Lectures delivered 

 before a Juvenile Auditory at the Royal Institu- 

 tion, Christmas, 1919. By Sir William Bragg. 

 Pp. viii+196. (London: G. Bell and Sons, 

 Ltd., 1920.) 6s. net. 



Though the original purpose of these lectures was 

 to arouse the interest of juveniles in the pheno- 

 mena of sound and their applications, they must 

 have appealed with equal force to those adults 

 who were so fortunate as to hear them. Here 

 the lectures are put into book form, with neces- 

 sary diagrams and additional dainty illustrations 

 which add much to the attractiveness of the text. 

 Even to the student who is conversant with the 

 ordinary text-books, much of the information must 

 be new ; this is particularly the case in the lecture 

 on "Sounds of the Country," in which are de- 

 scribed the methods by which sound-waves are 

 generated by insects and by the passage of wind 

 through the foliage of trees. In the following 

 lecture on " Sounds of the Sea " the most attrac- 

 tive subject is the gradual development of the 

 human ear from the simple rudimentary ear of 

 the fish. The interest of the subject culminates 

 in the last lecture on "Sounds in War," where 

 Sir William Bragg's first-hand knowledge is 

 applied to the description, in the simplest lan- 

 guage, of the ingenious devices used in locating 

 submarines, enemy guns on land by "sound- 

 ranging," and the direction of enemy mining 

 operations by the geophone. 



The Wild Unmasked. By F. St. Mars. Pp. 



376. (London and Edinburgh : W. and R. 



Chambers, Ltd., 1920.) 6s. net. 

 The author has a gift of picturesque vision and 

 delineation. There is no mistaking a strong 

 imaginative power. We see this in the very first 

 sketch of the interior of a wasp's nest and in the 

 life-history of an intrusive parasitic beetle. The 

 day's work of a sparrow-hawk, a water-vole's 

 flitting, a fight between a big rat and a stoat, 

 the adventures of an otter, a fight between a wild 

 cat and a fox — such are some of the subjects 

 of this romantic book. Prominence is given to 

 the competitive side of the struggle for existence, 

 which is one side of the truth, and many pages, 

 like some in Nature's book, are lurid. We are 

 not prepared to accept everything Mr. St. Mars 

 infers, such as the shrew's death from a sudden 

 noise, but the whole book expresses personal 

 observation. What is first-class in the book is its 

 vividness — it is not a study in still life, but 

 in strenuous, palpitating endeavour. What is 



dubious is the extent to which the author pushes 

 his anthropomorphism. With big-brained ani- 

 mals it seems a legitimate hypothesis, but in 

 regard to sea-anemones it palls. What is more 



NO. 2685, VOL. 107] 



than dubious, in our judgment, is the occasional 

 use of phraseology like " Mr. Passer," " Mrs. 

 Hare," and pet names for wild animals. They 

 strike a false note. The book would have been 

 finer if it had been less facetious. 



An Introduction to the Structure and Reproduction 

 of Plants. By Prof. F. E. Fritch and Dr. E. J. 

 Salisbury. Pp. viii -h 458 -f 2 plates. (London: 

 G. Bell and Sons, Ltd., 1920.) 15s. net. 

 The two parts of this work deal respectively with 

 the anatomy and the life-histories and reproduc- 

 tion of plants. A large number of the anatomical 

 figures are original, and although they vary in 

 quality, many of them are excellent for their 

 purpose. A few, however, show evidence of hasty 

 sketching. As a reference book for first-year 

 university students, it is the most useful we have 

 seen. Although its treatment is fuller in many 

 respects than an average first-year student can 

 compass, yet this is perhaps an error in the right 

 direction. Of special interest may be mentioned 

 the chapters on cell contents, secretory organs, 

 and anatomy in relation to habitat, as well as the 

 final chapter on heredity and evolution. The book 

 will form a very useful addition to the intro- 

 ductory text-books on structural botany. 



Annuaire pour I'An 192 1, public par le Bureau des 

 Longitudes. Pp. viii + 7io-h A42 -f B 17-t- C 69. 

 (Paris : Gauthier-Villars et Cie, n.d.) 8 francs 

 net. 



This widely used handbook contains all the old 

 well-known features, and in addition some new 

 ones. The astronomical, physical, and political 

 tables are very full ; there are useful maps of the 

 magnetic declination, inclination, and horizontal 

 force in France in 191 1, also full instructions for 

 constructing sundials, and a set of star maps, with 

 directions for their use. M. G. Bigourdan con- 

 tributes a useful and lucid article on the proper 

 motions and radial velocities of the stars, ad- 

 dressed to readers who have little previous know- 

 ledge of the subject. Gen. Bourgeois contributes 

 a biographical notice of Gen. Bassot (1841-1916), 

 whose name is well known among workers on 

 geodesy. The civil day (commencing at midnight) 

 is used throughout this handbook ; this system 

 will become universal at the beginning of 

 1925- 



Lectures on the Principle of Symmetry and its 

 Applications in all Natural Sciences. By Prof. 

 F. M. Jaeger. Second (augmented) edition. 

 Pp. xii + 348. (Amsterdam : Publishing Com- 

 pany "Elsevier," 1920.) 



That a second edition of this inspiring treatise on 

 crystallography has been issued so soon — the first 

 edition was reviewed in Nature for June 6, 1918 

 — is sufficient guarantee of its worth. Substan- 

 tially, the volume is the same as the earlier edition, 

 but the author has taken the opportunity to correct 

 a number of minor errors and to make a few 

 additions which the passage of time has shown to 

 be desirable. 



