PATHOGENIC BACTERIA. 271 



The poison is tremendously powerful (see page 164). It acts 

 as an excitant to the motor cells of the central nervous system, 

 especially the spinal cord. Bolton and Fisch have pointed 

 out the possibility that horses used for the preparation of 

 diphtheria antitoxin may be infected with tetanus, and have 

 tetanus toxin in the blood.* 



The activity of the poison is destroyed by heat and by 

 direct sunlight; various chemicals diminish its intensity. 



Antitoxin for tetanus has been prepared according to the 



Fig. 75. — Anthrax bacilli, erom a Pure Culture.! (X 1000.) 



principles employed for antitoxins in general. It has not 

 proved very markedly successful as a curative agent; but as a 

 prophylaxis, where aU patients are treated who have deep, dirty 

 wounds, and in a similar way in veterinary practice, it has un- 

 doubtedly proved of value. Unfortunately the disease is 

 seldom suspected until a relatively large amount of toxin has 



* Transactions of the Association American Physicians. 1902. 

 t The culture was derived from a case of malignant pustule in a tanner. 

 The lesion was excised promptly, and the patient recovered. 



