POISONS AND THEIR PREVENTION 203 



the anti-toxins, and furnishing yet another instance 

 of a substance exercising its immunising influence 

 over various toxins. 



This process of gradually acclimatising, as it 

 were, animals to a particular poison by repeated 

 doses of the same poison, recalls the old proverb, 

 " Seek your salve where you got your sore," and 

 brings us to a consideration of some of the primi- 

 tive antecedents of a practice which, at the present 

 time, promises to bring about so profound a revolu- 

 tion in the art of medicine. The modern system 

 of inoculation has, however, arisen quite without 

 reference to such antecedents, which latter were 

 not based upon any scientific laws or considera- 

 tions, but owed their evolution to local customs 

 and experience handed down from age to age by 

 tradition, and in many cases preserved through a 

 simple faith in the superstitions which surrounded 

 them. 



To such a category must be added the curious 

 superstitions indulged in by the native population 

 of Tunis regarding methods of preventing hydro- 

 phobia in persons bitten by rabid animals. Dr. 

 Loir refers to these primitive ideas on the art of 

 healing in a report of the work carried out at the 

 Anti-rabic Institute at Tunis, one of the many 

 centres for the prevention of rabies by Pasteur's 

 method which have been established in every 



