782 POPULAR SCIENCE MONTHLY. 



covery of the cause comes tlie question, How can this cause be 

 controlled ? How can its action be prevented ? Here, as Koch 

 says, men have begun at the wrong end of the problem. Since 

 the beginning of medicine the doctors have been experimenting 

 upon men to find a cure for consumption. The problem here is 

 too complicated, and in consequence little has been learned. Ex- 

 periment must begin, he says, with the bacillus itself. We must 

 grow it first in pure cultures in test tubes, in all manner of differ- 

 ent culture media and under all conditions of temperature and 

 light, in order to ascertain under what conditions it grows best 

 and under what conditions it can not grow. We must next sub- 

 ject it in the test tube to the influence of different chemical sub- 

 stances, and when some compound is discovered to Mil or hinder 

 the growth of the bacillus in the culture, then the substance must 

 be tried upon tuberculous animals to ascertain whether in their 

 bodies as in the test tube it will act to kill the bacilli without in- 

 juring the animal. When a substance fatal to the bacillus and 

 harmless to the animal is found, with all due allowance for differ- 

 ences between the animal and man, it may be tested on man. 



This, in brief, is but one important line of research, and clearly 

 it should be carried out thoroughly for every infectious disease. 

 A single link in the chain of procedure requires absolutely to be 

 welded by experiments upon living animals. With millions on 

 millions of human beings and animals suffering and dying yearly 

 for lack of this knowledge, no truly humane person can for a mo- 

 ment deny to an investigator the right to complete his work by 

 introducing this link. 



In view of the stupendous values involved it is clear that any 

 amount necessary of animal or human sacrifice and suffering is 

 wholly justified. Whether unnecessary suffering is inflicted is a 

 question which only the highest experts can adequately decide. 

 Prof. Bowditch * has so thoroughly discussed the subject of pain 

 caused by vivisection that we would pass it by without mention, 

 were it not for the fact that the public mind has been of late so 

 much abused by misstatement and exaggeration on this head. 

 Prof. Yeo's estimate, the most reliable we have, is that in every 

 one hundred experiments seventy-five are " absolutely painless," 

 twenty are as " painful as vaccination," four, as " painful as the 

 healing of a wound," one, as " painful as a surgical operation." 

 The pain of vaccination is altogether trifling, and that of the 

 healing of a wound after antiseptic treatment is also practically 

 nil. This leaves but one per cent of all experiments as painful to 

 any serious degree. During over ten years' active experience in 



* H. P. Bowditch. The Advancement of Medicine by Research. Science, July 24, 

 1896. 



