278 Beport on an Inquiry into the Nature, Causes, and 
removed with a capillary tube, and a fresh tube of cultivating- 
fluid is inoculated and placed in the incubator. And a similar 
procedure may be repeated for an almost indefinite period, if 
proper precautions be taken. The bacillus thus grown may be 
preserved in capillary tubes in certain stages of its existence for 
a very long time. I may now describe what these stages are, 
for modern research has shown that this organism passes 
through several distinct phases of existence, in all, however, 
preserving its power of germination under suitable conditions, 
as well as its infective property. 
As seen in the blood and tissues of animals dying of anthrax, 
the Bacillus anthracis is usually a short protoplasmic rod, 
measuring from one to four times the diameter of a human red- 
blood-corpuscle in length. These rods, in many cases, swarm 
in immense numbers in the blood, so that they may appear even 
to exceed the blood-corpuscles themselves in number, and by 
their presence they interfere with the normal coalescence of the 
blood-corpuscles and prevent normal coagulation of the blood. 
But it is not in every case of anthrax that the Bacilli present 
this appearance or are found in such numbers. Not uncom- 
monly they may be found in much smaller quantity ; and in 
some cases examined only four or five hours after death, the rods 
may be very much longer than those just described. This may 
possibly be due to growth after death of the animal. On minute 
inspection, the longer rods are usually found to be in process of 
division into two or more short rods of nearly uniform length. 
Fig. 1. — Bacillus antJiracis. 
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1. Rods of Bacillus anthracis as seen in the blood. 2. Portions of rods under cultivation. 
3. Groups of .spores. 1 and 2 magnified about 500 diameters. 3 about 700 diameters. 
The rods, which appear homogeneous and uniform, and blunt 
at the ends, increase in number by a process of elongation and 
transverse fission in the ordinary process of the disease within 
the body. If one of the rods which is in course of division be 
watched, it will be seen that having reached a certain length, a 
