170 
R. KOCH. 
reacts differently according to the different quantities of tuberculous virus. After 
an injection of pus containing few bacilli there arose on the peritoneum, as we have 
already seen, a disseminated tuberculous eruption, then|a development of little knots 
in the omentum and the spleen. But when masses of tuberculous bacilli were 
injected into the abdominal cavity of guinea pigs, then they were principally taken 
up by the large omentum. This rolls itself together and forms a horizontally-ex¬ 
tending, thick, sausage-like roll, which on intersection has the greatest resem¬ 
blance to an intersected, greatly swollen, and freshly caseous lymph-gland. In 
these white-yellowish, quite compact herds of the omentum enormous quantities 
of tuberculous bacilli are found, most of which are in a fine state of spore forma¬ 
tion. Besides this, as microscopic investigation shows us, the swollen spleen, the 
liver and the peritoneum are abundantly supplied with tuberculous bacilli, but 
the death of these animals occurs so early that the development of knots visible to 
the naked eye has not had time to occur. An effusion of liquid was not found in 
the abdominal cavity of guinea pigs, but was found in dogs and cats. On the 
contrary, in guinea pigs, such a large quantity of clear, faintly yellow liquid was 
found in the pleura that the lungs were compressed by it, and this caused the death 
of the animal. The guinea pigs usually died ten to twenty days after the injection. 
If a smaller quantity of cultur substance is squirted in, the course of the disease is 
of longer duration and there is then a development of visible, extraordinarily 
numerous tuberculous knots, particularly upon the peritoneum, on omentum, in 
the spleen and liver. The species of animals less subject to tuberculosis—dogs, 
rats, white mice—do not succumb even to the injection of abundant bacilli until 
after some months. But they then show also an unusually abundant tuberculous 
eruption in the abdomiual organs, but, on the contrary, less numerous knots in the 
lungs. 
Seventeenth Experiment: Reincultur from the tuberculous lung of a monkey 
(No. 11) cultivated for six months in eleven successive breedings, was rubbed up 
with blood serum and injected into ten guinea pigs, a half cubic centimeter into 
each. Two animals for counter experiment received, the one just such an injec¬ 
tion of pure blood serum, the other, which had a fresh, large wound from a bite, 
no injection at all. Of the animals which had received the injection, deaths 
occurred after ten, thirteen, sixteen, seventeen, eighteen days. The others, as well 
as the “ controlthiere*” were killed on the twenty-fifth day. In the guinea pig 
which died first the large omentum was rolled together, greatly thickened, and 
infiltrated with a yellowish-white brittle substance ; no knots were visible on the 
liver and spleen. The other animals of this experiment, as well those which died 
as those which were killed, had, besides infiltration of the omentum, already tu¬ 
berculous eruption of the spleen and liver. The controlthiere were perfectly 
healthy. 
Eighteenth Experiment: Reincultur of the tuberculous lung of a monkey 
(No. 11) cultivated for five and one-half months in ten successive breedings, 
rubbed up with blood serum, was injected into the abdominal cavity of two full 
grown vigorous cats. The one cat died after nineteen days. The omentum was 
rolled together, very much thickened, and infiltrated with a whitish compact mass. 
The serous covering of the intestines and the peritoneum had lost its lustre, the 
* Animals for counter experiment. 
