NATURE 



[December 19, 1907 



or of the marvellous evolutions of the caterpillar of 

 the swallow-tail when about to pupate. As the author 

 very pertinently remarks, to obtain photographs of 

 this description the artist has in most cases only a 

 single brief opportunity ; and if one single link in 

 the chain be missed, the whole series of pictures is 

 spoilt. Needless to say, the reader sees only the suc- 

 cesses ; the failures are labour lost. 



Among such an excellent series, it is difficult to 

 select particular figures for mention, but those of the 

 white admiral butterfly are especially noteworthy. 

 Equally instructive and interesting are the photo- 

 graphs of developing and retrograding vegetable-life; 

 more especially those connected with the fall of the 

 leaf — a progress of which comparatively few persons 

 know the physiological history. 



The senses of insects, illustrated with exquisite pic- 

 tures of antennje and the fly's " tongue," form 

 another chapter. The book closes with 12 photo- 

 graphs representing the monthly changes in a land- 

 .scape as seen from one particular spot — a fuller de- 

 velopment of the idea of photographing particular 

 trees in summer and again in winter. A better book 

 of its class we have never seen. 



(2) In the " Fairyland of Living Things " Mr. R. 

 Kearton, aided, as usual, by his brother's camera, 

 offers an attractive Christmas book, which should de- 

 light many households of yoimg people. In place 

 of confining himself to birds, the author includes in 

 his purview quadrupeds (both hot- and cold-blooded), 

 insects, and plants, and endeavours to interest his 

 clientele by dwelling on habits, instincts, and char- 

 acter rather than by describing structural details. 

 Whether the author has touched the right note must 

 bo left for the class of readers to whom he appeals to 

 decide; but we have never yet seen a "Kearton 

 book " that has not proved a success. R. L. 



Physiologisches Prctktiknm ji'ir Mcdiziner. By Prof. 



Ma.x Verworn. Pp. xii+202; illustrated. (Jena: 



Gustav Fischer, 1907.) Price 6 marks. 

 The practical class in physiology as known in this 

 country has never been adopted to the full in 

 Germany. There each student works out his own 

 salvation by independent laboratory work, and re- 

 search is started at an early stage in his career, as 

 a means to teach him methods and resource. Elab- 

 orate German handbooks have been written as guides 

 to such workers, most of them dealing with one 

 branch of physiology, and not with all. 



The aim of Prof. Max Verworn has not been to 

 write an ambitious work of this character, but to 

 furnish the average medical student with a guide 

 to certain fundamental exercises, most of which it 

 ought to be possible for each one to perform for 

 himself, possibly in a class, as is the English custom. 

 The remainder are appropriate for demonstrations. 



In such a book it is obvious that there should not be 

 over-specialisation, and thus we find in the subject, 

 snv, of the blood the study of its circulation closely 

 following on that of its chemistry. In this way the 

 various chapters see-saw between chemical and 

 physical matters. In a theoretical book this is an 

 'deal plan, but for a practical guide it has its draw- 

 backs. Prof. Verworn is so well known for his 

 writings on cells and what he terms " general 

 physiology " that it is not surprising to find that 

 some of the opening pages deal with this branch 

 of science, and simple exercises on galvanotaxis, 

 chemotaxis, and the like are introduced. 



In some cases the directions are purely practical, 

 ;md the descriptions of certain simple dissections are 

 most precise. In other ca.ses, theoretical matter and 

 ox|)lanations are interspersed. These necessarily deal 



NO. 1990, VOL. yy] 



with the subject very briefly, and the very briefness 

 is in some cases apt to cause bewilderment. The 

 description of the causes of blood coagulation cannot 

 possibly be clearly given in a single short paragraph. 



On the practical side we are surprised to find a 

 study of the pancreatic juice omitted, and on the 

 theoretical side no allusion is made to Emil Fischer's 

 work on the ultimate cleavage products of the pro- 

 teins. Some passages read as though the action 

 of pepsin and trypsin stopped at the albumose and 

 peptone stage. -Surely every student nowadays must 

 know something of polypeptides and amino-acids. 



The illustrations, as a rule, are clear and judiciously 

 selected, but the diagram of the absorption spectrum 

 of hasmoglobin is very imperfect; indeed, the whole 

 subject of blood spectroscopy is given in the merest 

 outline. 



Every teacher has, of course, his own ideas on the 

 relative importance of the different parts of his sub- 

 ject ; it is even possible that another reviewer might 

 commend what the present one feels inclined to 

 criticise. Two actual errors are, however, present ; 

 one is that fibrin is spoken of as a calcium com- 

 pound of fibrinogen ; the other is found in the descrip- 

 tion of the .\damkiewicz test for proteins, the colour 

 reaction being described as due to the carbohydrate 

 radical, whereas it has been proved to be due to 

 tryptophan. W. D. H. 



River Discharge. By J. C. Hoyt and N. C. Grover. 



Pp. viii+137. (New York: John Wiley and Sons; 



London : Chapman and Hall, Ltd., 1907.) Price 



2 dollars. 

 We have from time to time directed attention to the 

 hydrographic survey tliat has been in operation for 

 several years by the Geological Department of the 

 Llnited States Government. This survey is for the 

 purpose of ascertaining the water resources of the 

 country available for domestic use, irrigation or 

 power. 



The authors of the book now under notice have 

 both been engaged in the survey work, and give in a 

 thoroughly practical and useful way the result of their 

 experience, and of the methods adopted in carrying 

 out the work. 



The information both as to the methods and 

 the instruments used should be of great value to 

 engineers engaged in hydrographic work and to 

 students. The text is accompanied by twenty-four 

 illustrations showing the various forms of current 

 meters in use, the method of rating these, the floats 

 used, the cables and cages used for obtaining 

 velocities across wide rivers, weir stations, &c. 



The book is divided into six chapters, dealing re- 

 spectively with rainfall and evaporation ; instruments 

 used for obtaining velocities and depths; cable-station 

 equipments; wading stations; theory and practice of 

 measuring discharges ; weirs and weir formulas ; dis- 

 cussion and use of data ; together with seventeen 

 tables for facilitating the computations in various 

 hvdraulic problems. 



Construclioiis in Practical Geometry. By the Rev. 

 H. F. Westlake. Pp. viii + 50. (London: George 

 Philip and Son, Ltd., 1907.) Price is. 

 .\ cOLLRcrios' of simple geometrical constructions 

 without proofs, which is said to represent the mini- 

 mum knowledge of the subject required of candidates 

 in the Oxford and Cambridge School Examinations, 

 is here provided. .Ml the work can be done with a 

 ruler and pair of compasses. The diagrams are clear 

 and the instructions simple. A boy of twelve years 

 of age should have no diflficulty in mastering the 

 course of work. 



