248 THE DISEASES AND DISOEDEBS OP THE OX. 



which they have been contaminated with in their peregrinations 

 under the soil, seems very improbable ; and, indeed, Koch has 

 shown that the bacilli of anthrax, when mixed with earth in 

 which worms are placed, are not taken up by these creatures. 



These bacilli are always present in enormous numbers in 

 the blood of animals suflPering from anthrax. They may be 

 separated and washed with distilled water, alcohol, and ether, 

 and dried ; but still, if injected or otherwise introduced into 

 the blood or tissues of animals, they are capable of producing 

 anthrax, and cultivations of the germ may be made through 

 fifty generations with the same result. However, the bacilli of 

 anthrax have been subjected to such treatment by M. Pasteur 

 that if they are inoculated into animals they will produce a mild 

 form of the disease, from which the animal, as a rule, very 

 speedily quite recovers, being at the same time thereby rendered 

 secure against the ordinary virulent disease. Every year 

 thousands of animals are inoculated on the Continent in accord- 

 ance with the method discovered by M. Pasteur. 



This celebrated scientist directs that the germs are to be 

 exposed to a high temperature, viz. one of about 43 deg. C, 

 and also that they are to be passed through different species of 

 animals. The process is, of course, a very elaborate one. It 

 has been invariably found — and, indeed, is a well-known fact — 

 that the bacilli taken from the blood of sheep or cattle which 

 have died of anthrax always cause death when inoculated into 

 sheep or cattle, although, strange to say, after these bacilli have 

 been passed through white mice, they have lost much of their 

 virulence. The blood of white mice which have died of anthrax 

 does not kill sheep, but only produces a transient illness in 

 them, which, however — and here is the point of most extreme 

 importance — protects them against attacks of virulent anthrax. 



Further, it is to be remembered with care that the bacilli of 

 anthrax are capable of living and growing on the surface of the 

 soil, and they form spores, provided that they are well supplied 

 with oxygen. If sheep, or cattle, or other animals die of 

 anthrax, and their carcases are not properly disposed of, or if 

 fluids escape from their bodies and get on to the ground, the 

 bacilli thrive on the decaying matter present on the soil, 

 multiply, and even form spores. It is easy to see that such 

 land will continue to be a permanent source of infection to 



