274 



NA TURE 



[September 2, 1909 



with these regulations Dr. Smalian has enlisted the 

 services of a teacher in one of these schools at Halle. 

 The first half of the part before us is devoted to the 

 elements of botany, and the second to the rudiments 

 of zoologv, as exemplified by mammals and birds, 

 the plan being to describe one particular species of 

 plant and animal in considerable detail, and then to 

 discuss some of its relatives. The illustrations, 

 coloured and otherwise, are, if we mistake not, the 

 same as those used in the " Leitfaden," although in 

 certain instances reduced in size. This part is in- 

 tended for the instruction of the seventh class 

 (Lehrstoff der vii Klasse), so that in this case also 

 the various sections of the work are to be read in 

 consecutive order bv the different classes. Both text- 

 books appear well suited for their respective purposes. 



D/f Photographic. Bv W. Zimmcrmann. Pp. iv-h 

 164. (Leipzig : Quelle und Meyer, n.d.l Price 1.80 

 marks. 

 In twenty-three short chapters and an introduction 

 the author has provided a general guide for beginners 

 in photography similar to the numerous small guides 

 that we have in English, but differing from them in 

 being more fundamental and less detailed in the 

 matter of manipulation and precautions. The differ- 

 ence may be due to the more general diffusion of 

 elementary scientific knowledge in Germanv than in 

 this country. Formulas for the preparation of various 

 printing papers and plates are given, as well as in- 

 structions for their use, so that the volume is in no 

 sense a mere collection of instructions for the mani- 

 pulation of commercial products. This being as it is 

 and the volume so small, it is interesting to note the 

 selection that the author makes from the innumerable 

 alternatives now available. The formulae for 

 developers are in the following order : — Ferrous 

 oxalate, pyro-soda, pyrocatechin, nvrocatechin without 

 sulphite, hydroquinone, and mctol-hvdroquinone. 



In a chapter on " the chemical action of light and 

 development " the ionic theory is employed, a com- 

 mendable procedure if those for whom the book is 

 written may be presumed to understand it. But the 

 author evidently has his doubts, for he sets forth in 

 detail the chief fundamental facts upon which the 

 theory rests. In this case it appears to us that so 

 far as the very little chemistry introduced is con- 

 cerned, the explanations would have been more simple 

 and still sufficient if the facts had been dealt with on 

 the older plan, without reference to electric charges 

 and their migrations. We notice a few old-fashioned 

 errors with regard to actual products of certain chem- 

 ical changes, but on the whole the text is trustworthy, 

 interesting, clear, and very concise, and the illustra- 

 tions are apt. 



Science in Modern Life. Edited by Prof. J. R. Ains- 

 worth Davis. Vol. iii. Pp. ix+ 187. (London: 

 The Gresham Publishing Co., 1909.) Price 6.?. net. 

 The two earlier volumes of this work — which is to be 

 completed in six volumes — were noticed in Nature of 

 March 4 (vol. Ixxx.. p. i). The intention of the work 

 is to give a broad outline of the principles of science 

 and their relations to human progress and industrv. 

 The various departments of natural knowledge are 

 surveyed by eleven different authors, each of whom 

 is well qualified to deal with his particular subject. 

 The present volume is devoted chieflv to light, sound, 

 magnetism, electricity, and other branches of phvsics 

 not dealt with in the second volume; and, in addition, 

 about seventy pages are given to general biology and 

 botany. 



Mr. J. H. Shaxby's treatment of phvsics seems to 

 us to be appropriate to the design of the work and 

 calculated to create and foster interest in the subject. 

 NO. 2079, VOL. Si] 



Attention is given to the studies of recent years, such 

 as radiation pressure, radio-activity, Hertzian waves, 

 and wireless telephon\', and the style of description is 

 both readable and attractive. Dr. H. J. Fleure deals 

 with the diflicult subject of the cell and nuclear divi- 

 sion, and gives a general survey of simple forms of 

 life. Neither this section, however, nor that by Mr.. 

 J. -M. F. Drummond on botany which follows it, will 

 be intelligible without preliminary l-Liiowledge of the 

 subject, and will not appeal, therefore, to general 

 readers. 



-A work on various subjects, written by several 

 authors, is rarely uniform in character and scope, and 

 the present series of volumes is no exception to the 

 rule. In spite of this fact.'we are glad to express the- 

 hope that the work will be the means of bringing 

 problems and advances of modern science under the- 

 notice of a wide circle of readers. 



The Central Nervous System of Vertebrates. By 

 J. B. Johnston. Pp. 170. (Jena : G. Fischer, 

 1909.) 

 This interesting monograph appears in Dr. J. W. 

 Spengel's " Ergebnisse und Fortschritte der Zoologie. "■ 

 It gives an excellent account of the structure and 

 mechanism of the central nervous system founded 

 on morphological and physiological facts, as these 

 have been laboriouslv collected by the most modern- 

 methods by which the nervous elements have been- 

 examined. The author deals with the plan of reflex 

 mechanisms, he describes the architecture and local- 

 isation of the centra! ganglia and nerve-roots, and his 

 illustrations are drawn from morphological studies of 

 the simpler types. One of the most important sections 

 is No. vii., in which he discusses the functions of the 

 great divisions of the nervous svstem. Nowhere have- 

 we seen a better discussion of the relations and func- 

 tions of the cerebellum, or a more lucid account of 

 the remarkable deep connections of the auditory 

 nerves. The author has evidently received illumination 

 from the researches and constructive criticism of 

 Sherrington, while, as indicated by a good biblio- 

 graphy, he is acquainted with the literature of this 

 vast subject. The work is a valuable contribution to- 

 human and comparative neurologv. 



John G. McKendrick. 



Vorlcsungen iiber technische Mechaiiik. By Dr.. 

 .August Foppl. \'ierter Band, Dynamik. Dritte, 

 stark veriinderte -Auflage. Pp. viii4-422. (Leipzig: 

 B. G. Teubner, 1909.) Price 10 marks. 

 In this volume the vector equation of mass acceleration- 

 coirimonly known as Newton's laws is applied to the 

 "law of areas," the problems of harmonic and oscil- 

 latory motion, the brachistochrone, motion of a rigid 

 body, motion under no forces and motion of a top, 

 vibrations of elastic bodies and equations of motion of 

 hydrodynamics. The use of vector equations through- 

 out and differences of notation and terminology make 

 the treatment a little difficult for an English reader 

 to follow ; but it is clear that the author has fully 

 realised the subject of his book to be dynamics, not 

 the integration of differential equations. If excep- 

 tions exist, the most noticeable one is in the sections 

 dealing with cycloidal motion, the whole problem of 

 which can be solved, almost without writing down a 

 single equation, by showing the geometric properties 

 of the cycloid in a diagram where the author employs - 

 many formula. Among practical illustrations we 

 notice the reference to Schlick's balancing of marine 

 engines, while the reference to the Kegelbahn or 

 skittle-ground takes our thoughts back to the Father- 

 land, with its pleasant- afternoons spent in admiring 

 the view, drinking beer, and listening to the heavy 

 roll of the balls. 



