OHARBON AND THE GERM THEORY OF DISEASE 
143 
point the organism multiplies by division of the rods without the 
formation of spores. Such a cultivation after standing a month 
in contact with pure air loses all vitality, and the organism trans¬ 
ferred to fresh liquid is no longer capable of reproduction; the 
day before, however, and every preceding day its vitality was still 
retained, as was proven by its growth in such new cultivations. 
The virulence is entirely lost after the first eight days that the 
baccillus is kept at this temperature, and during these eight days 
the virus passes through' progressive degrees of attenuation. 
When a baccillus was thus obtained which had lost all virulence 
for the Guinea-pig, rabbit and sheep, it was found that its powers 
might be restored by cultivating it in the bodies of certain 
animals. It would still destroy a Guinea-pig but one day 
old, though it had no effect on one of six days, and by passing it 
through several successions of the former, it was soon able to de¬ 
stroy animals three to four days old, then those a week, a month 
or several years old, and, finally, the sheep itself. The organism 
had entirely regained its original activity. 
Having reviewed the recent investigations of charbon, some¬ 
what hurriedly it is true, it must be admitted that there is no con¬ 
tradiction, no inconsistency to be found in them; we see a rapid 
increase in our knowledge of the pathogenic agent, which prom¬ 
ises much for the future in regard to the whole class of the con¬ 
tagious diseases ; but this advance has directly followed from a 
study of thq Bacillus ant/iracis. The obscure points in regard to 
the preservation of the virus, its introduction into the body and 
its action on the organism have been made perfectly intelligible 
by the germ theory, and it is impossible to explain them on any 
other hypothesis. 
Before concluding, and at the risk of repetition, I offer the 
following facts which prove the pathogenic action of the B. an- 
thracis. 
1. The one-hundredth cultivation of the B. ant/iracis in a 
harmless liquid, if made under favorable conditions, is as virulent 
as the fresh charbon-blood. 
2. When the B. anthracis is removed by passing virulent 
liquids through a plaster filter, these liquids lose their activity. 
