492 THE WAR WITH THE MICROBES. 



To prepare these the solution of the toxins, which we have before 

 described, are injected into different animals, preferably horses, and at 

 the end of six to twelve weeks the blood of these animals is found 

 to yield a serum containing substances possessing both immunizing 

 and curative properties which we call antitoxins. The active principle 

 of this serum is present in a comparatively small quantity, but its influ- 

 ence is enormous. It does not appear to be a substance which directly 

 chemically neutralizes the poison, but counteracts its effects within the 

 animal in some unknown way. 



But some of our friends may ask, Were not these facts discovered 

 first by the use of animals, and hence has not this knowledge, though 

 of inestimable value to mankind, been too dearly bought? Yes, per- 

 haps, a score or two of guinea pigs and sweet, lovely rats and mice 

 have sacrificed their lives for humanity's sake. But this knowledge 

 could not have been gained in any other way unless by the sacrifice of 

 human life. What mother would hesitate to sacrifice a thousand 

 guinea pigs for the life of her child, or, on the other hand, would wish 

 her child to serve as the subject of experiment for others'? 



I have often been asked if the horses placed under this treatment 

 for the production of antitoxins suffer. I think not, and as an illus- 

 tration will relate an incident which has come under my own observa- 

 tion in the study of the antitoxins of the dread disease, tuberculosis. 

 A well-blooded horse, gentle in every particular, except that he would 

 run away upon the slightest provocation, seemed to be a suitable sub- 

 ject for some work. Accordingly he received an injection of the poison 

 of the tuberculosis germ, with the expectation that so high-strung an 

 animal would rebel against these pleasant familiarities. But he was 

 entirely too wise for this. He submitted quietly and seemed much 

 interested while by means of an hypodermic syringe a small quantity of 

 the poison was injected beneath his skin. A few days afterwards when 

 the operation was repeated it would have been reasonable to expect 

 that if there had been any discomfort the horse would have rebelled 

 against the procedure. Did this happen? Not by any means. As 

 soon as he observed the doctor appear with the syringe and bottle he 

 trotted toward him with pleasure, stood quietly looking around with 

 intelligence while the injection was made, and ever afterwards lent him- 

 self to the experiment with as much evident pleasure and interest as 

 that of the investigators, apparently thoroughly appreciating its object. 



It would hardly be fair to say that this dumb animal was endowed with 

 more intelligence than some of our ill-informed but well-meaning friends, 

 and yet would its actions not seem to indicate a high regard for scien- 

 tific work and disclaimer of suffering? 



Is it that they are instigated by a desire to inflict torture that scores 

 of investigators have sacrificed their lives in searching for the poisons 

 of dangerous bacteria and their antitoxins? Is it inhumanity which 

 spurs them on at imminent personal risk in their efforts, which are 



