D. B. WARD, M. D. 205 



action has disappeared some more toxin is introduced in 

 double the quantity and again the horse reacts in the 

 same way. This is repeated again and again with con- 

 stantly increasing amounts of the toxin until the horse 

 ceases to react, even when a half pint of the virulent cul- 

 ture is injected under his skin. The animal is bled and 

 the serum thus obtained is the antitoxin which is creating 

 such a stir in the medical world to-day. Experiments 

 with guinea pigs and rabbits show that with them it is 

 efficacious and statistics of its use in the human subject 

 seem to be favorable. We must wait, however, until the 

 smoke clears away a little before it is proper to pronounce 

 definitely upon its true value. A similar antitoxin to 

 tetanus has been prepared and successfully used in Italy 

 in several cases of lockjaw in the human subject. Now 

 the question arises — is there a similar antitoxin formed 

 in cases of consumption? A good many very brilliant 

 men are at work on this problem. 



There is the first great difficulty to overcome, that sus- 

 ceptible animals have not yet been immunized and no 

 way has yet been found to do it. You observe that we 

 may give diphtheria to a horse and he gets well, but if 

 we inoculate a susceptible animal with tuberculosis it 

 dies, and if we employ a naturally immune animal we 

 get no effect whatever. It is to be hoped that this diffi- 

 culty may be overcome and then we will be able to tell 

 whether blood serum from such animals will contain an 

 antitoxin or not. A way may be found to so modify the 

 virus of tuberculosis that the animal may recover, and 

 after repeating the process be found to be immune to 

 virulent cultures. If this can be done we will probably 

 be able to cure consumption or at least to protect those 

 who are especially susceptible to it so that they will not 

 take it. 



14:3 



