6o4 



NA TURE 



[April 30, 1908 



justified, and which immensely abbreviates the state- 

 ment of new definitions? After all, Mr. Russell's 

 definition, as here given, does not differ essentially 

 from the " umbral " definition (the first of the two 

 previously referred to). 



The synopsis is so condensed that it appeals rather 

 to specialists than to general readers. The latter, if 

 interested in the subject, will find it easier to read the 

 more important papers referred to on pp. 5-7, and 

 then gain a comparative view by studying the 

 synopsis. 



Prof. Shaw himself has made various contributions 

 to the subject, some of which are contained in the 

 present volume. His summary will doubtless do much 

 to further the study and comprehension of algebra in 

 general. G. B. M. 



MEDICAL PHYSICS. 

 Lchrhiich dcr medizinischen Phyzik. By Prof. H. 



Boruttau. Pp. viii + 282. (Leipzig: Johann .Am- 



brosius Barth, 1908.) Price 8 marl^s. 

 'T'HIS book is intended for medical students who 

 -»- have completed a course of general physics, and 

 is therefore limited to the study of the physical pro- 

 perties of tissues, the physical changes that take place 

 in the tissues, and physical instruments of importance 

 in physiology and pathology. In view of the slight 

 equipment of most medical students in mathematics 

 in Germany, as in this country, the treatment of the 

 subject is not mathematical, diagrams and simple 

 equations alone being used. Considering the variety 

 of the subjects treated, the book is of very modest 

 size. This result has been attained by keeping 

 theoretical discussions within the narrowest limits, 

 avoiding detail in descriptions of practical methods 

 and apparatus, and by the use of small but excellent 

 diagrams. 



According to the author, no similar book to this has 

 been published since that of Adolf Pick, the last 

 edition of which appeared more than twenty years 

 ago. As the scope of the book is therefore unusual, 

 a brief account of its contents may be useful. 



Chapter i. is introductory. Chapters ii. and iii. 

 are devoted to the general properties of tissues, which 

 are divided into fluids and solids, and include sections 

 on velocity, energy and its transformations, density 

 and elasticity of the different tissues, contraction of 

 muscle, the levers of the body, locomotion, deformi- 

 ties, blood pressure, pulse, blood flow, surface tension, 

 viscosity, osmotic pressure, and the secretion of urine. 

 Chapter iv. deals with gases in relation to blood and 

 respiration; chapter v. sound, including wave motion, 

 the analysis of sounds, hearing, speech, percussion, 

 and the sounds of respiration and the heart; chapter 

 vi. heat production and temperature, and their re- 

 lation to food, work and surface of the animal, con- 

 ductivity of clothing materials, and the laws of 

 thermodynamics; chapter vii. magnetism and 

 electricity : therapeutic use of electricity, the electric 

 properties of muscle and nerve, Rontgen rays, radio- 

 activity, N-rays ; chapter viii. optics : photometry, 

 mirrors, lenses, the eye, optical measurements, cor- 

 NO. 2009, VOL. 77] 



rection of optical defects, the microscope, immersion 

 lenses, polarimetrv, spectroscopy, calorimetry. Refer- 

 ences to original papers are given. 



A feature of the book is the inclusion of many 

 tables of physical quantities, e.g. comparative velo- 

 cities, densities and elasticities of tissues, specific 

 rotations, conductivities of clothing materials. 



That the book contains much useful information 

 not usually found in medical students' text-books is 

 undeniable, the section on blood pressure and pulse, 

 and that on the respiratory murmurs, for example, 

 but it is doubtful whether measurements of elasticity 

 of tissues, to which considerable space is devoted, are 

 of much value, owing to the fact that these tissues 

 show great variations according to their nutrition, 

 and that no tissue except bone is a true solid. 



In conclusion, it may be doubted whether a book 

 of this kind, dealing mainly with physiological sub- 

 jects from a phvsical point of view with a physical 

 classification, is entirely desirable. Physiologists, 

 after a large number of careful researches on the 

 physical phenomena of living tissues, have had to 

 confess that they are no nearer to the discovery ol 

 a physical basis of life. The student should, there- 

 fore, arrive at a truer view of the present position 

 of the science from books, which deal with the pro- 

 perties of the living organism as a whole, or as an 

 association of different organs, than from a book with 

 an essentiallv phvsical treatment such as this. 



J. H. R. 



OUR BOOK SHELF. 



Musee ostiologique; Etude de la Faune Ouaternaire, 

 Ostdometrie des Mammiferes. By E. Hue. Two 

 vols. Pp. xix + 50+186 plates. (Paris: Schleicher 

 Freres, 1907.) Price 24 francs. 

 To persons interested in cavern-research and cavern- 

 animals, and having no means of access to a museum, 

 these volumes — which are a monument to the industry 

 and perseverance of their author — will no doubt 

 be welcome, and afford adequate means of identifying 

 their " finds " with comparative ease. In this 

 country, however — apart from what may be the case 

 on the Continent — the number of such persons must, 

 we should surmise, be extremely small, and the sale 

 of the work consequently limited. On the other hand, 

 it may possibly be found of use to students of com- 

 parative osteology generally, without reference to 

 cavern-research. 



The plan adopted by the author is to take the skele- 

 tons of all the species of mammals the remains of 

 which are commonly found in caverns, and to arrange 

 their component elements in corresponding series, so 

 that all the skulls, all the humeri. Sec, are brought 

 together in associated plates. Each bone (except, of 

 course, those of the skull) and each tooth is figured 

 separately to scale, the scale in the case of each plate 

 being as large as circumstances permit. B\' means of 

 these figures to scale and measurements, Mr. Hue is 

 of opinion that it will be practicable for anyone to 

 identify such cave-bones — even when imperfect — as 

 may come under his observation. 



For this purpose a series of measurements for eacli 

 bone in the skeleton is recommended, the lines along 

 which these measurements should be taken being in- 

 dicated in a series of preliminary figures. By the aid 

 of a rule and pair of compasses, such measurcmenis 



