290 MICRO-ORGANISMS AND DISEASE [CHAP. 



the animals are inoculated with {/>) deuxieme vaccine : this 

 is chicken broth culture kept at 42 '3° C. for a week only. This 

 culture produces also a local effect with slight constitutional 

 disturbance, more pronounced than after the inoculation of 

 the premifere vaccine ; but the disturbance is only transitory 

 and the animals recover. Up to nine months such animals 

 are refractory against inoculation with virulent anthrax 

 blood. 



If the deuxifeme vaccine is used for the first inoculation, 

 the effect is more severe and may lead to fatal general 

 anthrax ; this deuxieme vaccine having been grown for one 

 week only at 42 "5° C. is therefore stronger, and is of a higher 

 degree of virulence than the premiere vaccine, which had 

 been grown at the high temperature for a fortnight. 



In all experiments with the anthrax bacilli it is necessary 

 to bear in mind that by passing the bacilli through different 

 species of animals they become endowed with different 

 qualities, and that bacilli which are fatal to some are not 

 fatal to all animals. While, for instance, the blood-bacillus 

 of sheep or cattle dead of anthrax invariably produces death 

 when inoculated into sheep or cattle, after passing through 

 white mice^ it loses this virulence for sheep and cattle. 

 The blood of white mice dead of anthrax does not kill 

 sheep ; it produces only a transitory illness, and the animals 

 are, for a time at least, protected against virulent anthrax. 

 The blood of guinea-pigs dead of anthrax produces illness, 

 sometimes death, in cattle, but as a rule does not kill 

 (Sanderson and Duguid), and the blood of the biscachia of 

 South America does not kill cattle, while it gives them a 

 transitory illness, and after this immunity for a time.^ Again 



' Klein, Reports of the Medical Officer of the Local Government Board, 

 1882. 

 ''■ Roy, Nature, December, 1883. 



