•96 PROTECTIVE INOCULATION 



The fact is reported to have been demonstrated by experiment 

 that the virulence of the attenuated virus can be easil}- res- 

 tored. Again, it has been shown by the investigations of 

 Chester and Neal, of the Delaware College Agricultural Ex- 

 periment Station, that a vaccine which succeeded at one time 

 subsequently proved fatal. The vital objection to this method 

 is, that it requires the use of the living bacteria which later 

 may become virulent and consequently cause a subsequent 

 outbreak. The scattering of pathogenic organisms, even in 

 an attenuated condition, should be avoided, if possible. It 

 must be admitted, however, that Pasteur's method has done 

 much good and helped to rob anthrax of much of its former 

 terror, especiall}- for the farmers of Europe. In America the 

 spread of anthrax has been checked in many districts by its 

 use. Dalrj'mple has recently pointed out its success in the 

 lower Mississippi valley. Notwithstanding, it is highly pro- 

 bable that the spreading of a knowledge of the specific cause 

 of this disease with that of proper disposition of dead animals 

 has also exerted much influence for good in checking its rav- 

 ages. 



In Germany and England the stamping-out system is con- 

 sidered superior to vaccination. According to Crookshank, in 

 England it is regarded as the only reliable means of suppress- 

 ing the disease. To this end rigid laws have been enacted. 

 In this countr}- as rigid measures as possible for its eradication 

 seem infinitely better than the general adoption of methods for 

 establishing a tolerance for its existence. 



§ 81. Law's modification of Toussaint's method. 

 Eaw has followed with marked success a modification of Tous- 

 saint's method. This consists in heating the blood taken from 

 an animal just dead from anthrax or killed in the last stages of 

 the disease, to the boiling point of water, grinding it in a little 

 sterile water or bouillon and injecting the resulting liquid. 

 The writer has employed this method in two outbreaks where 

 immediate action was imperative. In one of the epizootics 

 where it was tried, the deaths had reached three a day and the 

 astonishing result followed that not an animal died after the 

 injection. In the second outbreak the blood injection produced 



