THURSDAY, MAY 15, 1913. 1 NEW TEXT-BOOK OF PHYSIOLOGY. Principles of Human Physiology. By Prof. E. H. Starling, F.R.S. Pp. xii+1423. (London: J. and A. Churchill, 1912.) Price 215. net. same time it carries within it unmistakable and almost ineffaceable traces of its predecessors. An important feature of the book is the insertion of an introductory section on general physiology. This consists for the most part of two substantial chapters, one on the chemistry of cells and food materials, the other on elementary O one familiar with modern text-books of physical chemistry so far as it bears on physio Thoman physiology, the title of this work logy. The latter is a welcome innovation, for it Ex provides essential information that can otherwise be obtained only with difficulty. The bulk of the suggests something out of the common run. cellent "elements" of the subject, "manuals," and "text-books" exist in plenty. Indeed, Eng-volume is devoted to the stock subject-matter of a lish-speaking students are exceptionally fortunate in possessing as they do such a selection of trustworthy and often attractive presentations of the established facts of the science. At the same time many teachers have undoubtedly felt that the existing students' text-book, admirable as it is, is not in all things in tune with the times, and that a new presentation in which more attention should be paid to recently revealed or recently applied principles " would be a welcome acquisition. Prof. Starling's work is a response to this commonly-felt desiderium. To attempt to combine an up-to-date exposition of the traditional subject-matter of a manual of human physiology with a sufficiently wellintormed résumé of new and unfamiliar but appropriate branches of chemistry and physics, showing wherever available the connection between the one and the other, and in addition indicating the general trend of modern physiological investigation, implies qualifications rarely met with in one individual. It will be generally conceded that no one, whether from versatility of personal experience or from environment, was more competent han Prof. Starling to undertake the task. will be equally conceded that his reputation has not suffered in the achievement. In more respects than one the book represents an advance on previous works of a similar kind. It A word as to its history. Some fifteen or twenty years ago there existed an unpretentious little volume by the author entitled "Elements of Human Physiology." Admirably concise, clear in thought and style, no better epitome of physiology could be put in the hands of a student. The author subsequently enlarged this book, leaving the title unchanged. Although the enlargement went through a number of editions, it was never such an unqualified success as the original, at least from the reader's point of view. Like the new dress of the little girl who had made up her mind to cry, it was "either too long or too short." The present volume represents a further transformation, in which the whole work has been recast and greatly expanded, and the title changed. At the text-book of physiology, the material being grouped under two main headings, "The Mechanisms of Movement and Sensation" and "The Mechanisms of Nutrition." The author's firsthand experimental knowledge is especially brought out in the latter of these, while the former is mainly notable for the incorporation of Sherrington's work on the central nervous system. The book ends with a short section on reproduction. Apparently the author has not considered the time ripe for the introduction of a special section on growth. The book is illustrated with a wealth of pictorial matter, chiefly in the form of diagrams. While the work as a whole bears evidence of strenuous effort to bring it up to date (it contains a large amount of material comprised in no other general text-book of physiology), the process of modernisation is unequal. Thus, the value of the chapters on muscle and nerve has been enhanced by the inclusion of much recent investigation, especially of workers in the Cambridge school, but the partial selection of this material and the omission of other recent Continental work indicate that the author has failed to grasp some of the most suggestive teachings of nerve and muscle experiment. Again, the chapter on coagulation of the blood contains an admirable history of the coagulation question almost up to the date of publication, but the account of blood-platelets, with which coagulation is so intimately associated, is not only inadequate, but in regard to many statements quite misleading. The omission of any single section on the liver is difficult to explain. While a considerable amount of information (not always correctly indexed) on the physiology of the organ is scattered throughout the book, the structure and vascular relations of the liver are not described. One greatly regrets that the author has not seen his way to provide occasional references to original papers. A good scientific text-book has two classes of readers, students and research workers. To the latter a handy reference is most acceptable. For students the systematic mention of names and dates (the latter word might be written in capital letters) is an indispensable part of the apparatus of scientific education. On glancing over those names that are incorporated in the body of the text or attached to important illustrations, one cannot but remark how very English the experimental side of physiology has become. Breadth of outlook, to which the author lays some claim in his preface, has been secured not in every case by new and suggestive presentation of the materials to hand. Often enough, the author has depended rather on weight of added fact to illumine the intelligence of his readers. The consequence is that while he possesses a clear style that states scientific fact and argument without prolixity or ambiguity, his book makes at the best hard reading, its perusal being calculated to inspire respect rather than enthusiasm for the subject. Its obvious merits, however, outweigh all its defects. Textual errors and other discrepancies are present in not too great abundance. While no serious blunder of this kind has caught the eye of the reviewer, he would venture to protest against the retention of the Egyptian-like perspective of fig. 60. BRITISH BOTANISTS. Makers of British Botany: a Collection of Biographies by Living Botanists. Edited by F. W. Oliver. Pp. iv 332 xxvi plates. (Cambridge University Press, 1913.) Price 9s. net. THE Т T HE decision to publish the course of lectures on British botanists given at London University in 1911 was a very wise one, and Prof. F. W. Oliver deserves our sincere thanks for the trouble he has taken to produce so excellent a result. The volume is full of interest, and contains much concerning the lives and activities of some of the lesser-known British botanists that might otherwise have passed into oblivion. Modern botanists, after the perusal of the several biographies, may well reflect not only when they consider the remarkable energy of their distinguished predecessors, but also when they realise, as they now can, how great were the advances made in botanical science, despite innumerable difficulties, by the pioneers of the subject. The ten lectures of the course deal with the work of the following botanists: (1) Morrison (1620-83) and Ray (1627-1705); (2) Grew (16411712); (3) Hales (1677 1761); (4) Brown (17731858); (5) Sir W. Hooker (1785-1865); (6) Henslow (1796-1861); (7) W. Griffith (1810-45); (S) Henfrey (1819-59); (9) Harvey (1811-66); and (10) Williamson (1816-95). clude all the distinguished botanists to whos labours we owe the foundation of botanical scien in this country, it was wisely decided to supplement the lectures by the inclusion of chapters dealing with certain other botanists equally deserv ing of recognition as founders of the science. Eve with the inclusion of these worthies, namely, H (1716-75), Lindley (1799-1865), Berkeley (180389), Gilbert (1817-1901), Marshall Ward (1854 1905), the Edinburgh professors (1670-1887), and especially J. H. Balfour and Sir Joseph Hooke (1817-1911), the list is incomplete. Bentham, for instance, is an unfortunate omission, and it is t be hoped that it may not be long before a second edition is called for and that Prof. Oliver may carry out his intention of adding accounts of several other British botanists who should never be exclude. from a historical account of botany in Britain. Where the general level is so high, it is perhaps invidious to single out individual essays for special commendation, but of the lectures, Hales by Sir Francis Darwin and the account of Robert Brown by Prof. Farmer are of particular interest. T value of the volume is also very much enhanced by Sir W. T. Thiselton-Dyer's masterly account of Marshall Ward and by Prof. Bower's life of Sir Joseph Hooker, a task from its magnitude perhaps harder than that which fell to any other contributor to the volume. One of the chief reasons why we are grateful for this book is not so much that it tells us once more about men whose names are as household words, but rather because the value of the work done by those whose contributions to the science have been known only to the few can now be seen in its true light by all. Until the appearance of the book, how few of the younger botanists could have given a coherent account of the work of William Griffith, Henfrey, or Harvey? Griffith, as Prof. Lang points out, was a great botanist: "It is true that he failed to break through the limitations of his time and period, that he left no new and more correct general views to modify the science. But this is true of all his conte poraries; indeed, it is true of most botanists. T recreate the department of a science in which a man labours requires a combination of ability and fortunate chances that is given to few.” It is especially fitting to remember Griffith at the present day since he was a pioneer in the line of botanical work now known as ecology. Net only did he collect plants, but he frequently adopted the "plan of roughly manning each day's route and indicating the plants and associations of plants along the line of march." Ecological methods, it should be remembered, were also Since these biographies did not, of course, in- prominent in the teaching of John Hutton Balfe to Many passages of particular interest might be quoted from all of the chapters, but as the book to be appreciated must be read as a whole, we would rather commend it warmly to students of natural history and to those who would know of Britain's worthies. Thanks to the diaries kept by our earliest botanists and from the free use of contemporary information, the biographies are full of living personal interest. We can picture Robert Brown-facile botanicorum princeps, Britanniæ gloria et ornamentum-all the more easily and truly from the human touches in the following extracts from his diary for two consecutive days: "Feb. 7.-Before breakfast began the German auxiliary verbs. . . . At dinner about 3 pints of port... slept in my chair till nearly 3 in the morning. "Feb. 8. Before breakfast finished the auxiliary verb Seyn; to be. . . .” A. W. H. PRACTICAL AND THEORETICAL PHYSICS. (2) Practical Measurements in Radio activity. By (3) A Systematic Course of Practical Science for Price 15. 6d. net. (4) Practical Physics: a Text-book for Technical 1912.) Price 7s. 6d. net. (7) An Introduction to Mathematical Physics. By Dr. R. A. Houstoun. Pp. ix + 199. (London: Longmans, Green and Co., 1912.) Price 6s. net. (8) Die Elektrizität. By Prof. F. Adami. (Bücher der Naturwissenschaft, herausgegeben von Prof. S. Günther.) 9 und 14 Band. Pp. 126+4 plates + 180+ 12 plates. (Leipzig: Philipp Reclam, jun., n.d.) Price 1.50 marks. PINIONS differ as to the best mode of commencing instruction in (1) OPINI problem is of much importance, particularly in physics, in which subject, for some reason, students seem to find more than average difficulty. The author of this book has been convinced by his teaching experience that the most efficient method of presenting the elementary principles is by means of question and answer. His book therefore consists entirely of a long series of questions. To the more difficult of these questions answers are appended; to the easier the student is expected to supply his own answers. The subjects treated are just those usual in an elementary text-book, the greatest stress, however, being laid on mechanics, to which about half the book is devoted. As a While not questioning the undoubted value of question and answer in ascertaining the progress of students, it cannot be admitted that these form the function of a text-book. Question and answer should preferably be oral; they should also be mutual as between teacher and student. text-book the present volume is comparatively useless, principally on account of the lack of continuity and logical order which the method of presentation involves, but as a book of examples it may prove of considerable value. (2) The appearance of a book on radio-active measurements is very welcome. That it should come from the laboratory of Prof. Rutherford, and have for its authors two such distinguished workers on radio-activity, practically ensures its general adoption in advanced physical laboratories. It It can scarcely be doubted that the authors' assurance that so many and varied exercises in radio-activity can be performed with comparatively small quantities of active material will lead to the introduction of such measurements into the laboratory courses of many honours schools in physics. Most of the experiments described are already so included in Manchester, particularly with the view of the students ultimately taking up original research in this subject. The earlier part of the book is devoted to the theory and practical use of the electrometer and various electroscopes, and the treatment is both detailed and lucid. Much useful advice in the construction of home-made instruments is given, and the student is also told how to surmount the various difficulties which arise. Chapters iii. to vi. are devoted to the practical exercises previously referred to, the number which can be performed by means of simple apparatus being surprisingly large. The remainder of the book is intended for original investigators rather than ordinary students. Here the methods of making accurately standard radio-active measurements every the and branch of knowledge. The correct solution of the separation of radio-active substances are treated in considerable detail. These, together with the appendices concerning radio-active constants, ranges of particles, rates of decay, &c., cannot fail to be of the utmost use to those interested in the extension of knowledge in this sphere. Lack of space forbids as detailed a description as the work deserves, but it can be confidently stated that it will prove its own recommendation. (3) This is the first of a series of four little books on practical physics which the author proposes to publish. It is intended to form in schools a first year's course, and deals with measurements in mechanics of solids and fluids. The instructions are given in a very clear manner, and the student is told in every case exactly how to record the results. The arrangement of the book and the diagrams are excellent, rendering it quite one of the best of its kind. (4) This is another book on practical physics, but one of a much more extensive and advanced character. The experiments described are those on general physics and properties of matter which are suitable for the advanced classes in colleges and technical schools. A knowledge of the calculus is assumed, being used for the theoretical treatment of many of the exercises. Students are instructed in the methods of eliminating errors, and advised as to the precautions necessary to secure accurate results. The author has been very thorough in this respect, and his work compares favourably with the various standard text-books of practical physics. (5) Here is yet another book on elementary practical physics for use in schools. The two volumes deal respectively with mechanics, and heat and light. The method adopted is to ask a series of questions, the answers to some of them depending merely on theoretical knowledge and the others involving practical observations. In all cases space is provided in the book itself for the student to record the answers and results beneath the exercise itself. This certainly seems to be carrying this method of teaching a little too far, for in the case of the slovenly student the result will be that the book will be spoilt, while to the tidy student such spoon-feeding is quite unnecessary. The instructions given are rather meagre, and no diagrams are used for purposes of illustration. (6) Dr. Lecher's book is a simple treatise on physics specially intended for students of medicine and biology. The author has endeavoured to make the subject appeal to them by the frequent introduction of illustrations drawn from their own subjects. Naturally the book is quite elementary in character, but the scope is fairly comprehensive from a descriptive point of view. Some of the diagrams are rather old-fashioned, depicting, as they do, persons performing experiments, but thes are well and clearly printed, as is also the text (7) A book such as this of Dr. Houstoun's hos long been needed. Many students of physics have experienced considerable difficulty both in selec. ing and in understanding the various treatises on mathematical physics which they ought to read The present work will serve as an introduction to a variety of subjects, and the treatment is such that a student with a fair knowledge of the calculus and physics should be able to read it with comparative ease. The six chapters of the book deal respectively respectively with attraction, hydrodynamics, Fourier series and the conduction of heat, wave motion, electromagnetic theory, and thermodynamics. There is also a series of examples at the end of each chapter. One is inclined to think that the section on thermodynamics is scarcely so extensive as the subject deserves, at any rate in comparison with the space devoted to the other sections. Standard works on thermodynamics are, however, more readily available to the average student; consequently this defect is less serioa than it might otherwise have been. (8) In this little popular treatise on electricity Prof. Adami manages to describe in non-mathematical language various principles in electricity and their applications to important practical developments. The book is nicely got up, and the diagrams are exceedingly well produced. OUR BOOKSHELF. The Electron Theory. By Prof. Toshinojo Mizuno. Pp. 336. (Tokyo: Z. P. Maruya and Co., Ltd., 1912.) IN this book, which is intended for Japanese readers, Prof. Mizuno, of Kyoto Imperial University, gives the substance of a course of lectures which he delivered in 1911 at the Kyoto summer school. Beginning with the vacuum tube discharge, the author leads his readers through the various phenomena associated with the Zecman effect, Brownian movements, Lenard and Röntgen rays, up to the modern conceptions of the structure of the atom. In this connection the hypothetical forms of stable configurations are discussed at considerable length. There then follow fairly detailed sections on the constitution of the spectrum lines, on radio-activity, on the energy quantum theory, on the longitudinal and transverse mass of electrons, and the like. Towards the end the principle of relativity is introduced in connection with Michelson and Morley's classical experiments. The author makes no claim to any originality of treatment; but he has made himself master of the growing literature of the subject and has endeavoured to give a connected view of the many phenomena described. He is not satisfied with THIS is one of a long series of cheap, instructive books published by the firm of G. J. Göschen. The principal contents are the earth's potential gradient, forty-four pages; the electric conductivity of the atmosphere, thirty-five pages; electric currents in the air (including the ordinary fair-weather vertical current, electricity brought down by rain and snow, and lightning), twentynine pages; and the radio-active phenomena of the atmosphere, twenty-eight pages. Two other shorter sections deal respectively with the electric effects of sunshine and theories as to the source of atmospheric electricity. There are eighteen figures in the text, including some interesting Potsdam records of potential gradient during calm and disturbed weather. The author is a member of the staff of the Royal Meteorological-Magnetic Observatory at Potsdam, and is a recognised expert on the subject of which he treats. sidering its size, the book gives an excellent account, clear as well as concise, of the whole subject. German results loom somewhat more largely than they probably would in a text-book written in France or England, but there are a good many references to non-German writers, including Chauveau, Simpson, and C. T. R. Wilson. Con Leçons sur les Hypothèses Cosmogoniques projessées à la Sorbonne. By H. Poincaré. Edited by H. Vergne. Pp. lxx + 294. Second edition, with a Portrait and a Memoir on H. Poincaré by E. Lebon. (Paris: A. Hermann et Fils, 1913.) Price 12 francs. THE first edition of this work was given an extended notice in the issue of NATURE for May 2, 1912 (vol. lxxxix., p. vi). The present issue has been enriched by a portrait of Prof. Poincaré, and by the inclusion of a biographical notice and critical estimate of the eminent savant's work by M. E. Lebon, who has in addition made a few necessary corrections in the text. 4 Manual of Agricultural Chemistry. By H. Ingle. Third edition. Pp. vii+397. (London: Scott, Greenwood and Son, 1913.) Price 7s. 6d. LETTERS TO THE EDITOR. [The Editor does not hold himself responsible for opinions expressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts intended for this or any other part of NATURE. No notice is taken of anonymous communications.] Some Phenomena Connected with Reflected X-Rays. THE diagrams shown in Figs. 1 and 2 represent photographs obtained when X-rays were reflected on rock-salt and quartz. The spots lying on the left of the vertical line are due to the rays which have right are produced by reflected rays. passed directly through the crystal, while those on the It is easy to see from Fig. 2 that there are five spots due to the impact of the reflected rays. The middle spot and the two on the outside are more intense than the two others. The optical axis of the quartz specimen lies in this case in the plane of incidence forming an angle of 1' with the surface of the crystal. An explanation of the different spots of reflection shown in Fig. 2 can be given with the help of Fig. 3, can which is meant to show a cross-section of a hexagonal crystal cut at right angle to the optical axis. The points of intersection of the lines drawn in full may represent the positions of the molecules in the crystal. Considering this figure we assume that the more intense rays are reflected by the layers which are parallel to the lines drawn in full, and the weaker ones by layers which are parallel to the dotted lines. It is obvious that in the first case the molecules lie closer together than in the second. In addition, in Figs. 1 and 2 there are seen a series of lines which seem to converge towards the points of impact of the reflected rays, and are distributed in a way which is very similar to a spectrum obtained with visible light by means of two crossed gratings. Provided that in our case the phenomenon is due to an effect similar to that of crossed gratings, the directly reflected rays must be regarded as spectra of the order zero. On account of the diffusion of the lines, however, it is not possible at present to deduce from this the wave-length of the X-rays. E. HUPKA. Physikalisch-technische Reichsanstalt, |