May 9, 1884.] 
and, after application of aniline solution, by their 
comma form. 
As yet, twenty-two cholera bodies and seventeen 
cholera patients have been subjects of investigation. 
All these cases were studied for the presence of the 
specific bacteria, as well with gelatine cultivation as 
also in microscopical preparations, for the most part 
through cultivation in hollow slides; and, without ex- 
ception, the comma-shaped bacilli were found. This 
result, together with that obtained in Egypt, justifies 
the statement that this kind of bacterium is always to 
be found in the cholera intestine. 
For corroboration, moreover, investigations were 
earried on in the same way on twenty-eight other 
bodies (of which eleven had died from dysentery) ; 
the evacuations of one case each of simple diarrhoea, 
dysentery, and of a convalescent from cholera; then 
from several well people, as well as on animals dead 
from ulcer in the intestine, and pneumonia; finally, 
also with putrid masses of impure water (various 
samples from city sewage, water from very impure 
swamps, swamp scum, and impure river-water): but 
in not a single instance did it happen, either in stom- 
ach or bowels of the bodies of man or beast, in evacu- 
ations, or in fluids rich in bacteria, that the cholera 
bacteria was found. As by arsenic-poisoning a sick- 
ness very similar to cholera can be induced, an ani- 
mal was killed by arsenic, and, after death, the di- 
gestive organs examined for the comma bacillus; but 
with a negative result. 
From these results the further conclusion may 
be drawn, that the comma bacillus is peculiar to 
cholera. 
As to the connection of this bacillus with cholera, 
it was carefully stated in the last report, that there 
may be two views: 1°, that the condition of the 
organs of a person sick with cholera is such that 
this peculiar bacillus prospers; 2°, that the bacillus 
is the cause of the cholera, and that only when it 
makes its way into the bowels of man can the 
sickness take place. The first supposition is not 
allowable from the following grounds: it would be 
necessary to grant, that, when a man is taken sick 
with the cholera, this bacillus was already present in 
his organs, as shown by its universal presence in the 
considerable cases investigated in Egypt and India, 
two widely separated lands. This could not be the 
case, however; since, as has already been pointed out, 
the comma-shaped bacillus is never found, except in 
a case of cholera. 
Even in cases of bowel affection, such as dysen- 
tery and bowel catarrh, to which cholera very often 
supervenes, they fail. It is also to be considered, 
that, if this bacterium were always present in man, it 
would surely have been observed on some occasion ; 
which has not been the case. 
As the increase of this bacterium cannot be brought 
about in the bowels by cholera, the second supposi- 
tion, that it is the cause of cholera, only remains. 
That this is, in fact, the case, is shown unquestion- 
ably by other facts, and especially by its behavior 
during the progress of the disease. Its presence is re- 
stricted to the organ in which the disease is, — the 
SCIENCE. d719 
bowels. In vomit, they have, as yet, only been noticed 
in two cases; and in both, the appearance and alka- 
line reaction of the vomited fluids showed that the 
contents of the bowels, and with these the bacteria, 
had got into the stomach. In the bowels their history 
is as follows: in the first evacuations of the patient 
after the attack, as long as they have any form, very 
few cholera bacilli are present; the watery, odorless 
evacuations which follow, on the contrary, contain the 
bacilli in great numbers; while, at the same time, all 
other forms disappear almost entirely, so that, at this 
stage, the cholera bacilli are cultivated practically 
alone in the bowels. So soon as the cholera attack 
lessens, and the evacuations are again fecal, the com- 
ma bacteria disappear gradually, and are, after the 
convalescence, no longer to be found. The same 
is found to hold in cholera subjects. In the stomach 
no cholera bacilli were found. The bowels varied, 
according as death had occurred during the cholera 
attack or after it. In the freshest cases, the bowels 
showed a clear, red color; the inner lining of the intes- 
tines was still free from submucous extravasation ; and 
the contents consisted of a colorless, odorless liquid: 
the cholera bacilli were present in enormous masses, 
and nearly pure. Their distribution corresponded ex- 
actly with the degree and spread of the inflammation 
of the lining-membrane, the bacilli being generally 
not so thick in the upper intestine, but increasing 
toward the lower end of the smaller intestine. 
When, however, death has taken place later, the in- 
testines show signs of an important reaction. The 
lining is dark red in the lower part of the smaller in- 
testine, impregnated with extravasations of blood, and 
often dead on the outermost layers. The contents of 
the bowels are, in such cases, more or less blood- 
colored, and, in consequence of the re-appearance of 
the bacteria of decomposition, putrid and fetid. The 
cholera bacteria at this stage begin to disappear, but 
continue still to be present for some time in the solitary 
glands and in their vicinity, — a circumstance which 
first called attention to the presence of this peculiar 
bacterium in the bowels of the Egyptian cholera sub- 
jects. They entirely fail in such cases, only when the 
patient has lived through the cholera, and dies from 
the after-weakness. 
The cholera bacteria act exactly as other patho- 
logical bacteria. They occur only in their peculiar 
disease; their first appearance is when the illness 
begins; they increase in number with the severity of 
the attack, and gradually disappear as the illness 
wanes. They are found where the trouble exists; 
and their number, at the height of the disease, is so 
ereat, that their injurious effect on the lining of the 
intestines is explained. 
It might well be wished that it were possible, with 
these bacteria, to engender in animals a disease akin 
to cholera, that their causal relation to the sickness 
might be made the more clear. ‘This has, as yet, not 
been done: whether it will ever be done may well be 
questioned, as animals do not appear to be subject to 
cholera infection. If any kind of animal could take 
the cholera, then such a case would have been ob- 
served in Bengal, where, during the whole year, and 
