448 THE BACILLUS OF TYPHOID FEVER. 
sphere vitiated in this way lost, after a time, their usual activity and 
became emaciated, although they continued to eat greedily. When 
these animals were inoculated with a small quantity of a culture of 
the typhoid bacillus (0.25 to 0.5 cubic centimetre) they died within 
from twelve to thirty-six hours. The same amount of the typhoid 
culture injected into control animals produced no injurious effect. In 
the animals which succumbed to typhoid infection there was found a 
hemorrhagic enteritis, increase in volume of Peyer’s glands and of the 
spleen, and typhoid bacilli in the blood, liver, and spleen. The char- 
acteristic appearances of typhoid infection were more pronounced in 
the rabbits and guinea-pigs than in rats. Similar experiments with 
Bacillus coli communis gave similar results. The time required to 
induce this predisposition for typhoid infection was from five to 
seventy-two days for the rats, seven to fifty-eight for the guinea- 
pigs, and three to eighteen for the rabbits. Alessi found that the 
susceptibility to infection diminished after a certain time, and sug- 
gests that in a similar way man may become habituated to breathing 
an atmosphere containing sewer gases. 
Pus-Production by Typhotd Bactlli._The literature relat- 
ing to the typhoid bacillus includes many observations as to its 
presence in accumulations of pus in various parts of the body—often 
ina pure culture. It has been found in a considerable number of 
cases of periostitis secondary to typhoid fever, in purulent syno- 
vitis, and in abscesses in various parts of the body. 
Dmochowski and Janowski (1895), as the result of a review of the 
literature and a painstaking experimental research, arrive at the con- 
clusion that even in abscesses, occurring in typhoid fever cases, in 
which only the pus cocci are found, it is probable that the typhoid 
bacillus originated the process resulting in abscess formation. They 
assert that the typhoid bacillus dies out in a comparatively short 
time in abscesses which are directly due to its presence, and that 
often it may be found in the abscess walls when its presence can no 
longer be demonstrated in the purulent contents of the abscess cavity. 
