214 



SCIENCE 



[N. S. Vol. XXVI. No. 659 



diseases increases, we find that not only are 

 they to be found in the tropics, but also to a 

 greater or less extent in our own country. 



The book is divided into several parts, 

 beginning, of course, with the usual intro- 

 duction, but in this case including a discus- 

 sion of tropical hygiene. The treatment of 

 this subject denotes a familiarity with condi- 

 tions as found in the tropics obtained only 

 by experience, and if the advice given were 

 followed, it would materially decrease the 

 amount of sickness and the number of deaths 

 occurring among those living there. 



That portion of the book which treats of 

 mosquitoes, though brief, is well worth study- 

 ing for those likely to be brought into contact 

 ■with either malaria or yellow fever. 



The book is written in a narrative style, the 

 usual text-book description of the subjects 

 being given, but with sufficient personal ex- 

 periences interspersed to lend an added in- 

 terest to the subject under discussion. 



The book is divided into three parts, the 

 ■first part dealing with " Systemic Diseases 

 (Chiefly Bacterial in Origin)." This section 

 is mainly concerned with a discussion of the 

 infectious diseases. 



Under the heading of Cholera, the descrip- 

 tion of bacteriologic technic to be used for 

 diagnostic purposes is faulty and not clear, 

 and leaves the impression that a mere novice 

 could make a diagnosis, whereas, as is well 

 known, cases arise which offer great difficulty, 

 from the presence of other spirilla giving 

 similar reactions and only differentiated by 

 agglutination or animal experiments. The 

 author lays considerable stress on the use of 

 the anti-cholera serum prepared by the Japa- 

 Tiese, which, he says, has an anti-toxic action. 



It is surprising to note, as is stated, that 

 Haffkine's prophylactic had never been used 

 as a curative agent for plague; its use for 

 such a purpose would certainly seem con- 

 tra-indicated. Under the same heading, the 

 author recommends for the agglutination test 

 that " the serum be diluted with normal salt 

 solution to a proportion of 1:3." It is very 

 doubtful whether agglutination obtained with 

 such a dilution would be of any value. 



The chapter on malaria is vrritten in a 

 more detailed way than those on the other 

 diseases. 



The author apparently believes in the in- 

 fectious nature of beri-beri, accepting the 

 work of Wright, though giving rather full 

 abstracts of the report of Baron Takaki of 

 the Japanese navy, who ascribes the marked 

 decrease in the number of cases in the Japa- 

 nese navy to a change of diet consisting of 

 the addition of barley and an increased 

 amount of meat to the usual rice diet. 



In the chapter on yellow fever, considerable 

 space is justly given to the work of Reed, 

 Carroll, Agramonte and Lazear, composing 

 the board appointed by the government for the 

 study of yellow fever. 



The second part is taken up with a discus- 

 sion of diseases produced by animal parasites. 

 The chapter on ankylostomiasis is excellent, 

 the author here again detailing his own ex- 

 periences. The remainder of this section is 

 taken up with a discussion of filariasis, try- 

 panosomiasis and those diseases produced by 

 parasites peculiar to the tropics. 



The third part treats of diseases of unde- 

 termined causation and of the skin. Under 

 this heading is to be found a brief description 

 of such diseases as acute febrile icterus, 

 mycetoma, tropical splenomegaly and of some 

 of the parasitic skin diseases. 



At the end is a list of articles recommended 

 for diagnostic purposes which would un- 

 doubtedly be of great value for any practising 

 physician. 



A perusal of the book would be of benefit to 

 any one likely to come into relation with 

 tropical diseases. 



James W. Jobling 



eockefellek institute for 

 Medical Reseaech 



DISCUSSION AND CORRESPONDENCE 



ON THE EFFECTS OF MAGNESIUM SULPHATE ON 

 THE GROWTH OF SEEDLINGS 



A RECENT issue of Science contains a letter 

 from Professor Oscar Loew, which, for some 

 unaccountable reason, is entitled " a correc- 

 tion." I have read the letter carefully several 



