DISTRIBUTION OF BACTERIUM COLI COMMUNE 7 
one instance already noted. A good deal, however, depends on the character of milk 
used ; it is very necessary that it should not have reached too high a temperature 
during sterilization. Hence it is best to sterilize three times in Koch's sterilizer 
at ioo° C, rather than in the autoclave. In the latter case, I found frequently that no 
coagulation took place, in cases in which it was very marked in milk, which had not 
been heated above ioo°. All the examples of B. coli isolated gave indol to a greater 
or less degree ; whether this test, also, is as useful as has been supposed has been 
questioned.* 
The occurrence of fermentation, formation of gas and acid, in media contain- 
ing certain sugars seems to be the first and most important of these characteristics ; 
this is what one would expect, as the reaction appears to be the simplest. For 
example, in a glucose-gelatine shake culture, when the gas is once produced, its 
TABLE lla 
Description 
Date 
Dilution 
No. < 
n Plate 
No. per c.c. 
West Derby Sand Bed Ef- 
fluent 
West Derby Sand Bed Effluent 
(another sample) ... 
Effluent from West Derby 
Dibdin Bed, filtered through 
experimental Filters. 
No. 1 Filter 
Dec. II, 
Dec. 11, 
Dec. 12, 
1899 
1899 
'899 
OI 
•01 
undiluted 
; 
I 
3 
:i 
3 
258 
$ 
.58 
225 
193 
18 
18 
3i 
1 1 
•3 
25,800 
27,200 
27,600 
I 5,800 
22,500 
19,200 
No. 2 Filter 
Dec. 12, 
1899 
undiluted 
■ 1 
2 ■ 
No. 3 Filter 
Dec. 12, 
1899 
undiluted 
; 
3 
8 
10 
5 
No. 4 Filter 
Dec. 12, 
1899 
undiluted 
; 
H 
1 5 
16 
Manchester Crude Sewage 
Open Septic Tank Liquor. 
Manchester 
West Derby Dibdin Bed Ef- 
fluent 
West Derby Dibdin Bed Ef- 
fluent 
Dec. 12, 
Dec. 12, 
Nov. 8, 
Nov. 9, 
1899 
1899 
1899 
1899 
d odd 
3 
I 
3 
; 
3 
1 
I 
++ 
53 
37 
26 
27 
3+ 
114 
105 
1 1 1 
M 
1 4,400 
5.300 
3.37° 
2,600 
2,700 
3,400 
1 1,400 
10,500 
1 1,100 
3,400 
3>7°° 
3,500 
3,3oo 
* A. W. Peckham, Abstr. Cm 
ralbl.f. Bait, 
xxiii, p. 9 
86. -j- A very low figure for c 
rude sewage. 
