a aie 
TRANSACTIONS OF SECTION D. 857 
half an inch in diameter, was found at the seat of inoculation. On the thirteenth 
day a second large tumour appeared in front of the former. This gradually in- 
ereased in size, and was found to contain caseating pus. About a week later no 
further increase in size could be noted. The animal appeared to be emaciated, but 
after some weeks was strong and fat. Although he was not so successful with the 
other twelve rabbits that he had used in this research, they often exhibited sym- 
ptoms of great interest. In one case the rabbit lived for thirteen days; in most 
cases, however, they died in 60-70, hours after inoculation, or perhaps lived no 
longer than the control-rabbit. After treatment with either pepsin or trypsin the 
following peculiar appearances could be observed in their spleens : 
(1) Whereas in the control-rabbit, as was usual with virulent anthrax, the 
bacilli were seen as short rods, in the research animals the bacilli were often to be 
found arranged in the long chains so characteristic of attenuated anthrax. 
(2) Whereas in the control-rabbit phagocytes containing bacilli can only very 
rarely be found, in the rabbits treated with pepsin and trypsin, in some cases, 
spleen-phagocytes containing bacilli are particularly numerous. 
(3) The chains of bacilli sometimes showed signs of degeneration, staining very 
irregularly, some joints being stained, others remaining nearly colourless. In 
. other experiments that he has performed since, the author has seen degenerated 
‘ 
bacilli at the seat of inoculation, but nowhere else. 
Another interesting point is that rabbits whose life is prolonged by treatment 
with ferment will occasionally show diarrhcea for some days before their death. 
The author has only noticed this in two or three cases. 
With regard to these facts, it may be noted that the attenuated appearance of 
the bacilli, the signs of phagocytosis, the elongation of the incubation period, and 
the diarrhoea, can all be regarded as indications that the power the animal possesses 
of resisting the onset of the disease has been increased by the injection of ferments. 
On the other hand, the striking irregularity in the results must be noticed. Often 
an animal treated with pepsin or trypsin will die as soon as, or even sooner than, the 
control-animal. The bacilli in its spleen may be not longer, but shorter than usual, 
and phagocytosis, and the enlargement of the spleen that generally accompanies it, 
may be completely absent. It is a general rule that opposing forces produce irregu- 
lar results ; and the widely varying effects of ferment injection led me to look for 
some conflicting tendencies. Possibly, on the one hand, the ferment was harmful 
to the anthrax bacilli; but, on the other hand, also harmful to their host, and so 
lowered its bactericidal power. He attempted to decide whether this was the 
explanation of his results in the following way. So far as is known, acquired 
tolerance ean be obtained far more readily against poisonous proteids than against 
any other kind of poison. Since pepsin and trypsin either are proteid in nature, or 
appear to be more allied to proteids than to any other class of bodies, would it not 
be possible to obtain an acquired tolerance on the part of the rabbit against them, 
leaving unaffected their action on the later-arriving anthrax bacilli? The first 
experiment to test this had a result apparently favourable to the idea. On April 6 
three rabbits, A, B, and C, received 4, 3, and 13 c.c. respectively of a ‘08 per cent. 
solution of trypsin.! The next day 5,1, and 13 c.c. respectively of a ‘1 per cent. 
solution were injected into each rabbit, and on April 8 they received respectively 
4, 2,and2c.c. On April 7 they were all inoculated with anthrax. A control- 
rabbit was also inoculated, and succumbed after about sixty hours. He has in his 
notes that the anthrax culture was ‘ deuxiéme vaccin,’ but as it had been repeatedly 
transmitted from culture to culture (on agar-agar) for at least eight months, and 
generally killed rabbits in thirty-six to forty-eight hours, without any doubt it 
had in some measure, at all events, recovered its virulence. All three rabbits had 
diarrhceea. <A, that is to say the rabbit which had most trypsin, died a week after 
the anthrax inoculation. The other two recovered. B had diarrhoea for some 
days, but this had vanished, and its temperature was normal on April 18. At 
this date C’s temperature was 40°-4, and it still had diarrhoea, which only dis- 
1 The trypsin employed was obtained from Schering’s Griine Apotheke, Berlin. 
1890. 3K 
