October 25, 1912] 



SCIENCE 



561 



hardly necessary to take it up page by page, 

 as is so often done with volumes intended for 

 students, and point out various slips, typo- 

 graphical and otherwise. The author dis- 

 claims any idea of expressing the whole truth, 

 but feels the obligation of saying nothing but 

 the truth. This limitation, not always felt by 

 writers of popular works on botany, may be 

 responsible for some of the omissions noted. 

 After a particularly good discussion of the 

 relation of botanical science to society, one 

 chapter each is devoted to the cell, the seed, 

 the root, the leaf, the stem, growth, the flower, 

 plants and animals and the origin of organic 

 form. This latter chapter is distinctly pro- 

 Darwin ; in fact, there is little if any reference 

 to the recent work along this line and the 

 whole discussion smacks strongly of Zweck- 

 mdssiglceit. The reason for adding as an ap- 

 pendix a lecture delivered in 1875 on the 

 plant as a source of energy is not manifest. 

 Unfortunately there is no index. 



a. T. M. 



The Toxicity of Caffein: an Experimental 

 Study on Different Species of Animals. 

 By William Salant and J. B. Eieger. 

 Bureau of Chemistry Bulletin 148, pp. 98. 

 The Elimination of Caffein: an Experimental 

 Study on Herhivora and Carnivora. By 

 WiLLLiM Salant and J. B. Eieger. Bureau 

 of Chemistry Bulletin 157, pp. 23. 

 One can not help feeling, on looking 

 through these two bulletins filled with a 

 wealth of detailed investigation on so im- 

 portant a drug as caffein, that the authors left 

 no stone unturned in their quest for truth. So 

 many experiments were made that their pre- 

 sentation in abstract form is extremely diffi- 

 cult. However, a few of the salient features 

 can be briefly stated. 



The principal object of the work describd 

 in the first paper seems to be the determina- 

 tion of the toxic and of the fatal dose of caf- 

 fein for the rabbit, guinea-pig, cat and dog. 

 Theoretically this is simple. But as the au- 

 thors have shown, the toxicity of caffein, like 

 that of any other drug, depends upon such 

 conditions as the age of the animal, its diet. 



the method of administering the drug, and 

 still other factors which complicate the ques- 

 tion of toxicity. Only after the most exten- 

 sive investigation can all of the questions 

 taken up in the bulletin be answered with any 

 degree of certainty. 



So strongly has the infl.uenee of diet, method 

 of administration, etc., on the action of a 

 drug been emphasized that one can not help 

 wondering whether the toxic and fatal doses 

 of caffein are really definite quantities for 

 more than one set of experimental conditions. 

 The conservatism of the authors, as exempli- 

 fied in the following statement from page 91 

 of their bulletin, is certainly commendable: 

 "... the most striking effect of caffein ob- 

 served in the work herein reported was the 

 comparatively wide range of variation in the 

 resistance of individuals of the same species 

 to this drug. This was found to be the case 

 even when the conditions of experimentation 

 were appro:^imately uniform. . . ." 



In their second bulletin the authors present 

 their work on the elimination of caffein. 

 They found that " Caffein administered sub- 

 cutaneously, by mouth, or intravenously, is 

 eliminated in part unchanged, in the urine, 

 into the gastrointestinal canal, and into the 

 bile. . . ." 



Since the appearance of the above bulletins, 

 at least two other pharmacological researches 

 have been published which show how ex- 

 tremely careful the investigator must be be- 

 fore coming to final conclusions regarding the 

 toxicity of a drug. In the Proceedings of the 

 Society for Experimental Biology and Medi- 

 cine^ Kleiner and Meltzer describe some ex- 

 periments on the reduction of the toxicity of 

 strychnin by the simultaneous administration 

 of large quantities of fluid. They state " that 

 the toxicity of strychnin is definitely reduced 

 not only when it is administered in great di- 

 lution, but also when saline or water is ad- 

 ministered nearly simultaneously in other 

 parts of the body, thus, perhaps, diluting the 

 poison within the body. . . ." 



Traube" states that the pharmacological ae- 



^Vol. IX., p. 101, 1912. 



' Biochemische Ztschr., Bd. 42, p. 494, 1912. 



