koch’s method with tuberculosis. 
79 
ment at government expense in a national school ot veterinary 
medicine, he had satisfied himself that th^ survivors of an at¬ 
tack of anthrax did not contract a second attack when exposed 
or inoculated. He, therefore, in 1880, instituted experiments 
on sheep by heating the virulent anthrax fluids to 55 0 C., for 
from ten to fifteen minutes, and with this product inoculating 
the animals to be protected. In a short time he had ten animals 
thus inoculated, that resisted all ordinary inoculations with 
anthrax virus. Then a crucial experiment was instituted at 
Alfort, in which twenty sheep were inoculated with his heated 
anthrax liquids, and unfortunately four of the number died of 
anthrax; Sixteen survived and these after proved insuscep¬ 
tible to anthrax. The partially unfortunate result and Tous- 
saint’s increasing ill health would appear to have deterred him 
from further advance in the same line, and no other European 
observer seemed then to appreciate the value of his results. 
Experiments were, however, being made in the same di¬ 
rection in America. Dr. Salmon was, in 1880, experimenting 
on fowl cholera and I was dealing with swine plague, both 
for the National Department of Agriculture. Each, independ¬ 
ently of the other, undertook to test the protective action of 
the ptomaines. Dr. Salmon’s observations on the chicken dis¬ 
ease led to negative results, the ptomaines being either volatile 
or destructible by heat. 
In my experiments with swine plague I was more fortunate. 
. But to show my views at that date and the results I obtained 
I shall quote from the Department of Agriculture Report on 
Contagious Diseases of Animals. 1880-1, pp .135-146. 
“ BACTERIA INTOXICATION AND BACTERIA INFECTION. 
“ In all diseases caused by microphytes, there are two as¬ 
sociated but distinct deletereous agents to be taken into 
account: 1st, the organism which is introduced from without 
and multiplies in the bod) r of the patient; 2d, the chemical 
products elaborated by the growth and increase of the import¬ 
ed organism at the expense of the vital liquids. The two 
have been aptly named bacteria infection and bacteria intox¬ 
ication. Each may be injurious and even fatal, yet each has 
