IN THE VICTORIAN ERA 21 



motest parts of the world cannot be overesti- 

 mated. 



Methods for the prevention of disease have, 

 however, not been confined to the elaboration 

 and employment of modified or weakened bacterial 

 viruses ; the subject has been still more recently 

 approached from another and quite different side. 

 This new departure we also originally owe to 

 France, although its practical development has 

 been worked out in Germany. 



It was in 1888 that two Frenchmen, Richet 

 and Hericourt, communicated a memoir to the 

 Comptes rendus of the Academy of Sciences, 

 describing the curious results they had obtained 

 with rabbits purposely infected with a disease 

 microbe, the Staphylococcus pyosepticus. Some of 

 the rabbits died after being inoculated with this 

 micro-organism and some remained alive, and 

 they proceed to point out how it was that such 

 different results were obtained. Before the in- 

 oculations were made some of the animals received 

 injections of blood taken from a dog, which a 

 few months previously had been infected with 

 this same microbe, but had recovered. The 

 rabbits which received the dog's blood all survived 

 the inoculations, whilst those which did not, 

 succumbed in every case to the action of the 

 Staphylococcus pyosepticus. So struck were the 



