ANTITOXIN 287 



velop antibodies similar to those developed by the body 

 in its struggle with disease. For example, if small doses 

 of the toxin developed by the bacteria of diphtheria are 

 repeatedly injected into a well horse, his tissues will 

 develop the antitoxin which antagonizes diphtheria, so 

 that he will quickly become immune to the disease while 

 retaining perfect health. If this process is continued 

 until the maximum amount of antitoxin has been devel- 

 oped, the blood of the horse becomes richly supplied with 

 it. It may then be used to supply antitoxin to a person 

 stricken with diphtheria. The destruction of tissue 

 which goes on while the body itself is preparing anti- 

 toxin is thus avoided, and its presence in sufficient 

 amounts immediately insured. In this way, the microbes 

 are overcome before they have time to overwhelm the 

 body or to cause serious destruction of tissue. As a re- 

 sult, the fever goes down and the person quickly 

 recovers. 1 



In consumption. In diseases like consumption, where 

 the disease is of such slow progress as to be chronic, 

 there is sufficient time to stimulate the body to produce 

 antibodies. In addition to such improvement in gen- 

 eral health as can be brought about by fresh air and 

 good food, the production of antibodies may be further 

 stimulated by the actual injection into the patient of 

 toxins in the form of the dead bacilli of the disease. 

 The increased amount of toxins in the body stimulates 

 it to make enough antibodies to overcome them. 



Infection. A disease, to be infectious, must be pro- 

 duced by a microbe which has the power of invading 

 the body, of multiplying therein and of giving rise to 



1 Thus far the method of producing antibodies has been dis- 

 covered for only certain of the infectious diseases, but it is un- 

 doubtedly only a question of time when the list will be greatly 

 extended or even made complete. 



