from an Afjricxdtural and Veterinary Point of Vieic. 79' 
German, observed these bodies in 1849, Davaine and Raver in 
1850; and Brauell, of the Dorpat Veterinary School, in 1856,. 
also noticed them. But these likewise did not realise the 
significance of their presence in the blood of anthrax-stricken 
animals. 
It was not until 1863, that Davaine, having had his attention 
once more drawn to these organisms in the blood, by Pasteur's 
discoverv of the butyric ferment, was led to examine whether 
thev, if introduced into the blood of an animal, would also play 
the part of a ferment ; as, if so, this would explain the rapid 
infection of the blood in an animal which had received into 
its veins, accidentally or experimentally, a certain quantity of 
this ferment. Inoculating sheep and rabbits with blood taken 
from a diseased sheep a few hours after death, he constantly 
found the organisms, which he named Bacteria ; though when 
inoculated with blood from the infected animal before these rods 
were visible, and while it yet appeared in health, no effect was 
produced. " In the present state of science," wrote Davaine 
at this time, " no one would think about going beyond these 
corpuscles to seek for the agent of contagion. This agent is 
visible, palpable ; it is an organised being endowed with life> 
which is developed and propagated in the same manner as other 
living things. By its presence and its rapid multiplication in 
the blood, it undoubtedly produces modifications in that fluid, 
after the manner of ferments, which speedily destroy the infected 
animal." This was the first direct evidence that a contagious 
disease is produced by a microscopic organism, and the discovery 
converted into a fact what was before only a hypothesis. 
Davaine's announcement was not received without doubt and 
hesitation by some, and two experimentalists — MM. Jaillard and 
Deplat — were unsuccessful in arriving at the same results by 
experiment, and consequently sought to refute his conclusion. 
Paul Bert also opposed his view, and corroborated that of Jaillard 
and Deplat. " I can," he said, " destroy the bacteria in a drop of 
blood by means of compressed oxygen, inoculate with it, and 
reproduce the disease and cause death without any appearance of 
bacteria. Therefore they are neither the cause nor the necessary 
effect of splenic fever. It is due to a virus." And so the con- 
troversy went on. 
At this time, a young physician in Germany, Dr. Koch,, 
began to study the anthrax bacilli or bacteria, as they have been 
indifferently termed ; though Cohn, another German investi- 
gator, was also at work in defining their morphology. Koch- 
traced the life-history of the Bacillus anthracis, as it is now 
designated, and showed how widely it was distributed throughout 
the blood and organs, and especially the spleen of animals which. 
