October 28, 1904.] 



SCIENCE. 



563 



eluding original researches by G. S. Gea- 

 • ham-Smith, M.A., M.D., D.P.H., Camb., 



and T. S. P. Strangeways, M.A., M.K.C.S. 



Cambridge University Press. 1904. 



The recent stxidy of the mechanism of im- 

 munity begun by Bordet and Ehrlich has 

 opened an entirely new chapter in biological 

 science and has already yielded some practical 

 results of great interest and importance. None 

 of these practical aspects of the new science 

 has been so prolific of immediate results as the 

 study of the precipitins. These specific proteids 

 are developed in the animal body by injection 

 of foreign proteids, as blood-serum, milk, bac- 

 terial emulsions, etc., and their presence in 

 the blood of the treated animal is indicated 

 by the fact that when the blood-serum is added 

 in vitro to the alien blood or to the bacterial 

 emulsion used in the injections, a precipitate 

 occurs from the union of the newly-developed 

 precipitin and the foreign proteid. The pre- 

 cipitins are highly specific, acting only on the 

 proteid injected, so that when a rabbit has re- 

 ceived several injections of human blood, its 

 serum precipitates the proteids of human 

 blood, but not those of beef, sheep or any 

 other lower animal blood. The first applica- 

 tion of this principle has developed the 

 medico-legal serum test for blood which has 

 become fully established as a reliable test 

 in forensic cases. 



Nuttall and his associates were among the 

 first to see the possibility of establishing by 

 means of the precipitin test a far more ac- 

 curate scheme of relationships in the animal 

 kingdom than has been possible by any other 

 method, and the results of their studies, ex- 

 tending over a period of three years, are 

 presented in detail in the present volume. 



The elaborate scope of the work may be 

 judged by the fact that Nuttall himself pre- 

 pared in the rabbit anti-sera for the bloods 

 of thirty different animals and records no 

 less than sixteen thousand tests on the blood 

 of nine hundred animals. Only the barest 

 outline of the many important results of 

 this extensive work can here be indicated. 



In general, Nuttall succeeded in establishing 

 a close blood relationship in different classes 

 of animals which zoologists have grouped to- 



gether chiefly on anatomical grounds. Among 

 the most interesting of these relationships is 

 that between the Anthropoidea. It is a some- 

 what startling verification of the consanguin- 

 ity of man and the higher monkeys that the 

 blood of the chimpanzee gives 90% as much' 

 precipitum with humanized rabbit serum as 

 does the blood of man himself, while the blood 

 of lower monkeys yields only one fourth or 

 one third as much. The chimpanzee thus 

 appears much more nearly related to man 

 than to the common RhcEsus monkey. Another 

 interesting result is the observation that anti- 

 pig serum is remarkably diffuse in its action, 

 affecting considerably the blood of primates 

 and showing that the porpoise has correctly 

 been called the ' sea hog.' 



Numerous conflicting results are recorded, 

 which is not a matter of surprise, considering 

 that the specimens of blood were collected on 

 blotting paper, often under great difficulties, 

 and sent by mail from nearly all parts of the 

 world. As the author states, only a beginning 

 of the study of blood relationships has been 

 accomplished and much remains to be done 

 in determining the exact standing of different 

 animals in their respective classes. It is of 

 fundamental importance to have established 

 the fact that the precipitin test is universally 

 applicable as a method of zoological rating, 

 and may have much influence in elucidating 

 many problems of evolution. It may be sug- 

 gested that new points of view may, perhaps, 

 be secured and former results be effectively 

 controlled by comparing- the action of anti- 

 sera for the same blood prepared in other ani- 

 mals as well as in the rabbit, which is the 

 animal almost exclusively employed by work- 

 ers in this field. 



The method of estimating the degree of 

 reaction by measuring the bulk of precipitate 

 is one of the many important contributions of 

 the author to the technics of serum work. 



Graham-Smith contributes an extensive 

 study of anti-sera among lower vertebrates 

 and arthropods,' and an important critical 

 study of the medico-legal application of the 

 test. This investigator more than any other 

 has demonstrated the possible sources of error 

 in the medico-legal use of the test, so that 



