September 25, 1919] 



NATURE 



71 



conclusions based upon them. That there is a 

 radical divergence of testimony 'is evident from 

 the fact that by one school of thought coastal 

 drift is attributed entirely to wave action, and 

 by another to current flow. By the author no 

 doubt is entertained that, as a whole, waves are 

 the more important agency, and in this view of 

 joint action we are disposed to concur. 



In dealing with shorelines, the author rejects 

 the German system of numerical notation, and 

 classifies them broadly as submergent, emergent, 

 neutral, and compound, with a cycle of develop- 

 ment passing from young to mature and old. 

 Each of the four classes is dealt with at length, 

 and there are apposite examples, illustrated by 

 photogr.iphs, charts, maps, and diagrams, which 

 will repay study. Fjords are not recognised as 

 an indication of land subsidence, but are attri- 

 buted to glacial action, and it is interesting to 

 note the author's opinion that "any careful 

 analysis of the process of marine erosion must 

 lead to the conclusion that marine planation is 

 possible without coastal subsidence." 



The book covers a fairly wide area, and is 

 written with the intention of assisting the engin- 

 eer, the geologist, and the geographer. .As affect- 

 ing the first-named profession, the difficulty of 

 reconciling the conflicting views of so many 

 eminent authorities seems to us almost insuper- 

 able. There is scarcely any problem which causes 

 the harbour engineer more perplexity and anxiety 

 than that of forecasting the effect on the shore- 

 line of a structure projecting into the sea, and in 

 the present state of our knowledge — or ignorance 

 — the evidence available is often capable of quite 

 contradictory interpretations. No doubt further 

 investigation will throw more light on this 

 bafl[ling question, but, for the present, it is beset 

 with obscurity. 



The volume is an excellent addition to the 

 literature of physiography, and it fulfils a special 

 function in classifying much fragmentary and 

 detached information not readily accessible'. 



Bryssox Cunxingh.xm. 



MAMMALIAN PHYSIOLOGY. 

 Mammalian Physiology: A Course of Practical 

 Exercises. By Prof. C. S. Sherrington. 

 Pp. xi+156 + ix plates. (Oxford: At the 

 Clarendon Press, 1919.) Price 12s. 6d. net. 

 ■nPHE publication of Prof. Sherrington's prac- 

 ■*• tical course of mammalian physiology will 

 surely be recognised as an event of first-rate 

 Importance for the teaching of physiology and for 

 medical education. 

 _ Many teachers must long have felt the limita- 

 tion imposed by the use of the frog for practically 

 all class-work on living animal organs. The 

 experiments possible to students were re- 

 stricted to certain aspects of the subject; some 

 were liable to be retained in the course which 

 had mainly historical interest, and others were 

 apt, in unpractised hands, to degenerate into 

 exercises in fine dissection. Nor had the tech- 

 NO. 2604, VOL. 104] 



nical facility thus acquired much relation to the 

 later requirements of the medical equipment. 



The introduction into class teaching of the sur- 

 viving carcass of the decerebrated or decapitated 

 cat effects a great liberation. The student can 

 observe for himself the main phenomena of mam- 

 malian function. The technique is in most cases 

 relatively so simple that attention is concentrated 

 on the observation of the result ; at the same 

 time, it has real value as an introduction to 

 surgical manipulations. 



The course opens with exercises on isolated 

 mammalian plain muscle — intestine, spleen, and 

 artery — and on the perfused heart of the rabbit. 

 They involve no very new departure, but the 

 methods given require simple apparatus only, and 

 are admirably adapted to give successful results 

 in the hands of students. Here, too, as through- 

 out the book, each exercise is given the maximum 

 educational value by the explanatory and historical 

 comments. 



From Exercise IV. onwards the decerebrated or 

 decapitated carcass is used. Starting with rela- 

 tively simple experiments on the arterial blood- 

 pressure, the course leads to more elaborate 

 demonstrations of the effect of nerve-stimulation 

 on the vascular mechanism and the activity of 

 the respiratory centre, of vascular and somatic 

 reflexes, and ultimately, when the requisite dex- 

 terity has been acquired, to such relatively exact- 

 ing experiments as that on the stimulation of pan- 

 creatic secretion by secretin. In each exercise 

 the opportunities are fully used for incidental 

 observation of important phenomena, not directly 

 connected with the main object of the experiment. 



The student who conscientiously follows this 

 course must emerge with a wealth of experience 

 in the methods of physiological observation, and 

 a vivid apprehension of vital phenomena, which 

 no amount of reading or even of witnessing pre- 

 pared demonstrations could give. Prof. Sherring- 

 ton himself points out that the method leaves to 

 the individual teacher a wide choice of valuable 

 exercises, beyond the representative series which 

 he has been able to accommodate within the limits 

 of his course. He opens, indeed, a new vista of 

 possibilities to student and teacher alike. 



The value of the book is greatly enhanced by 

 the admirably clear drawings of dissections and 

 apparatus. The records reproduced, nearly all 

 taken from experiments made in the class, give 

 convincing evidence that the exercises are well 

 within the compass of the keen student. The 

 last exercise of all, that on the determination of 

 the opsonic index, .seems to lie curiously outside the 

 general scope of the course, and to have no clear 

 connection with the opportunities offered by the 

 brainless mammal. Doubtless experience has shown 

 that its inclusion has some special advantage. 



Not only students and teachers, but also those 

 engaged in original investigation, have abundant 

 cause for gratitude to Prof. Sherrington for the 

 care and labour which he has expended on putting 

 his methods and experience at their disposal. 



H. H. D. 



