6io 



NATURE 



[October 27, 1892 



it always does when such a subject is treated of in brief 

 space — to be of great assistance to the reader. 



The index is good, and the book is a valuable addition 

 to Public Health literature. 



OUR BOOK SHELF. 



Lehrbuch der Botanik nach dent gegenwdrtigen 

 Stand der Wissenschaft. Bearbeitet von Dr. A. B. 

 Frank. Erster Band : Zellenlehre, Anatomic und 

 Physiologie. 8vo. 670 Seiten, mit 227 Abbildimgen in 

 Holzschnitt. (Leipzig : Wilhelm Engelmann, 1892.) 

 This is essentially a fifth edition of Sachs's renowned 

 " Lehrbuch der Botanik," the fourth and last German 

 edition of which appeared as long ago as 1874. An 

 English edition, emended and augmented by the trans- 

 lator. Dr. S. H. Vines, was published in 1882. Now, 

 ten years later, Dr. Frank has written a completely new 

 work. As the author tells us in his preface, he was 

 requested in 1890 to prepare a new edition of Sachs's 

 book ; but he has adopted the wiser course of making 

 himself responsible for the whole. Nevertheless, free use 

 has been made of Sachs's excellent illustrations, upwards 

 of ninety out of the two hundred and twenty-seven having 

 been taken from that source, " because the author could 

 not replace them by better ones." About sixty are bor- 

 rowed from other authors, and about seventy of them are 

 original, or at least Dr. Frank's own, for some of them 

 have appeared elsewhere. A number of them are reduced 

 from Frank and Tschirch's " Wandtafeln." Certainly 

 the book is admirably illustrated. In the limitation and 

 arrangement of the material the author has followed Sachs 

 in a general way, though he has separated the physiology 

 and anatomy from morphology and classification. The 

 two latter branches are to be dealt with in a second 

 volume, promised early next year. So far as the present 

 volume is concerned, we can strongly recommend it to the 

 student familiar with the German language. It is 

 written in a clear, succinct style ; and, so far as we have 

 been able to test it, it is well up to date. Dr. Frank is 

 well known as a writer and teacher of botany, and 

 especially for his researches and experiments relating to 

 the nutrition of plants. The sources of the nitrogen of 

 plants and symbiosis are two subjects to which the author 

 has devoted much attention, and they are discussed in 

 some detail from his own standpoint. We are glad to 

 see that copious and complete references are given to the 

 books and articles of the principal writers on the various 

 subjects, whose views are discussed or adopted. Un- 

 fortunately there is no index, and it is not easy to find 

 one's way through the table of contents. True, a " care- 

 fully prepared " index is promised with the second volume, 

 but a separate one to each volume would be far more 

 convenient and time-saving. It is not as though the 

 second volume was a continuation of the first ; and it is 

 to be hoped that the author and publisher will even yet 

 see their way to provide this facility for using the work. 



Arithmetical Chemistry. Part II. Book B. By C. J. 

 Woodward, B.Sc. (London : Simpkin, Marshall, 

 Hamilton, Kent, and Co. Birmingham : Cornish 

 Bros., 1892.) 



The student will find in the present edition of this work 

 what is practically a new book, as the author has enlarged 

 and entirely rewritten the original publication. The 

 opening lessons treat of analyses, the formulae of minerals, 

 Dalton's law of partial pressures, gas analysis, &c., and 

 are on the whole satisfactory. The introductory portions 

 of the lessons, which embody the principles involved in 

 the exercises, and contain typical examples fully worked 

 out, are clear, as a rule, and the exercises themselves are 

 both suggestive and useful. The same may be said of 



NO. 1200. VOL. 46] 



the concluding part of the book, wherein are briefly dis- 

 cussed atomic weight determinations, and the various 

 means of controllmg atomic weights, calorific power and 

 intensity, heats of formation, dissociation, and gaseous 

 phenomena, comprising the kinetic theory, diffusion, and 

 absorption by water. 



The intermediate lessons on molecular weights are, 

 however, not up to the standard of the others. It is not 

 made plain when discussing Avogadro's law that a 

 vapour density observation, when possible, is the decisive 

 mode of fixing the molecular weight of a compound. 

 The vague description of the apparatus used in measuring 

 osmotic pressure can only confuse the reader, and loose 

 statements such as "solutions behave as gases," p. 51, 

 must have the same effect. The relationships established 

 in connection with the vapour-pressures of solutions 

 only hold if the dissolved substance is practically non- 

 volatile, this point is omitted, and the definition given of 

 equimolecular solutions is not the one in common use. 

 Indeed, the entire treatment of the properties of solutions 

 as applied to molecular weight observations, although it 

 may perhaps enable the student to solve problems, is 

 much too fragmentary and loosely put together to give 

 him an adequate idea of what is Known on the subject. 

 It may also be pointed out as somewhat late in the day 

 to give a few of Kopp's conclusions as an account of 

 specific volume. 



Among minor corrections it may be noted that on p. 6, 

 in the first erratum, solvent should be solution, vapour- 

 tension might often be replaced by vapour-pressure, 

 xylol should be xylene, and amyl benzoat should be amyl 

 benzoate, on p. 48. " Ostwald's Solutions " might be in- 

 cluded in the list of English works to which the student 

 is referred. 



The book contains an index, a list of answers, and a 

 collection of the questions in arithmetical chemistry set 

 at the Honours examinations of the Science and Art De- 

 partment, and at the B. Sc. examinations of London 

 University. A portion of the author's ABC Five figure 

 logarithms is presented with this edition. J. W. R. 



Lessons in Heat and Light. By D. E. Jones, B.Sc. 



(London: Macmillan and Co., 1892.) 

 The success of a previous work on " Heat, Light, and 

 Sound," has led Prof. Jones to extend the two former 

 parts, and publish them separately for the use of schools 

 and junior classes in colleges. As an introduction to the 

 study of experimental physics, the book cannot fail to be 

 of great value. The principles of the subjects are very 

 clearly stated, and the experiments from which they have 

 been deduced are fully described. Most of the experi- 

 ments may be easily performed by students, the instruc- 

 tions being sufficiently clear to guarantee success. 

 Numerous arithmetical examples, partly selected from 

 the author's " Examples in Physics," are added at the 

 ends of the various chapters. The physiographic bear- 

 ings of the subject of heat have been brought well to the 

 front ; thus the origin of the Gulf Stream, trade winds, 

 and the formation of rain and snow are explained. Many 

 of the diagrams have been carefully drawn to scale, in 

 order to give the student an idea of the dimensions of 

 the apparatus which may be conveniently employed in 

 performing the experiments. 



Ele7nents of Magnetism and Electricity . By John Angell, 

 F.C.S., F.I.C. (London: Collins, Sons, and Co., 

 1892.) 

 This is a new edition of one of the best-known text- 

 books for use in connection with the classes under the 

 control of the Science and Art Department. The book 

 calls for no special remark ; but the fact that a hundred 

 thousand copies have already been disposed of seems to 

 demonstrate its usefulness. Experiments and illustrations 

 are its special features. 



