312 OFFICIAL REFUTATION OF DR. KOCH’S THEORY 
established. Still the facts which have been brought to the 
notice of the Committee seem to point to the probability that 
the special organism to which such virulent properties are 
ascribed by Dr. Koch will, sooner or later, be demonstrated to 
be one or other of the various curved forms ordinarily found 
in the alimentary tract in health, the growth of which has been 
favoured by the exceptional conditions which exist in the intes- 
tine during an attack of cholera. 
11. As regards the third point—the evidence as to the 
causal connection between the comma-shaped organisms and 
cholera—perhaps the most striking circumstance which gave 
support to the theory advanced by the German Commission in 
India was that referred to by Dr. Koch, that, when visiting 
one of the native quarters in the suburbs of Calcutta, in which 
an outbreak of the disease had occurred, he discovered comma- 
shaped bacilli in the village tank, and, further, that the disease 
diminished simultaneously with the diminution of the commas 
in the water. 
12. Regarding this phase of the question, Drs. Klein and 
Gibbes write : 
“We have had the opportunity, in connection with Dr. D. 
D. Cunningham, to make an examination of the water of some 
of the tanks in Calcutta, with reference to this very question 
of the comma-bacilli. 
‘*The same tank that plays such a conspicuous part in 
Koch’s report above mentioned was visited on the 26th No- 
vember. It is surrounded by native huts in which about 200 
families are living. There had occurred one case of cholera in 
this bustee about the first week of the month of November. 
The water of this tank was very dirty, particularly all along 
the shore, and the people around the tank, as is customary, 
made use of the water for all and every kind of domestic and 
other purposes, including drinking. 
«‘A sample of this water was taken from near the shore, 
where it appeared particularly impure, about twenty yards 
from the house in which the cholera case had occurred, and 
the microscopic examination revealed undoubted comma- 
