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than five-lmndred and sixty-eight persons, and fifty thousand 

 animals perished from this fell disorder. Here again M. Pasteur 

 detected the special fungoid growth or bacillus, which produced 

 these disastrous results, and found that by cultivating the germs 

 in different media, he was able so to weaken or modify their 

 virulence, that vaccination with this attenuated virus protected 

 healthy animals from a severe attack of the disease, without 

 seriously affecting their health. 



In a celebrated test experiment, which was watched with the 

 keenest interest by scientists as well as by many practical men, M. 

 Pasteur inoculated twenty-five sheep out of a flock of fifty, and 

 after their recovery from the slight illness thus produced, he 

 publicly inoculated the whole flock with the ordinary virus of 

 anthrax. The result was precisely in accordance with his pre- 

 dictions ; within forty-eight hours the twenty-five uninoculated 

 sheep were dead, while those which he had previously inoculated 

 with the weakened virus, were alive and well. No less than one 

 million seven hundred thousand sheep, and ninety thousand oxen, 

 have been vaccinated with the preventative virus during the last 

 few years, the result being that the mortality from this plague, 

 which formerly averaged ten per ceut., has been reduced to less 

 than one per cent. The system of preventative inoculation is now 

 universally adopted in all those districts in France where anthrax 

 was formerly prevalent. 



But, perhaps, M. Pasteur's most brilliant achievement is in 

 connection with his experiments for the prevention of the awful 

 disease called rabies, for, although he has not yet identified its 

 special bacillus, he has found that by cultivating and weakening 

 the virus of the disease, a lymph is produced, with which he be- 

 lieves dogs or other a limals may be effectually protected by vacci- 

 nation from rabies. He has also greatly advanced our knowledge 

 of this dire disease, for whereas the poison was formerly supposed 

 to exist only in the saliva of the rabid animal, M. Pasteur has 

 traced it definitely to the nerve centres. An animal inoculated 

 with virus from the spinal marrow of a rabid animal developes the 

 disease far more rapidly than one inoculated only with the saliva. 

 The fact that the nerve centres are the seat of the disease goes far, 

 according to M. Pasteur, to explain the cause of his anti-rabic 

 treatment not being invariably successful. The length of time 

 occupied by the virus from the tooth of a rabid animal in reaching 

 the nerve centres varies according to circumstances, and should the 

 central nervous system be affected before the inoculation with the 

 weakened virus takes place, the latter is of course valueless. 

 The difference of opinion on the Pasteurian method of dealing with 

 the rabies is very great, and the various arguments for and against 



