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These results are shown in graphic form in Diagram 7.
The Table shows that on one occasion the number of B. coli was greater in the effluent from
the 13-foot coke-bed than in the corresponding sample of raw sewage. In nearly all the other cases
the crude sewage contained the larger number. Nevertheless, although on an average the bacterial
treatment of the crude sewage effected a reduction in the number of B. coli, the number actually
remaining in the effluents was very large—usually more than 100,000 per c.c.
(c) Number of Stores of B. Enteritidis Sporogenes (Klein).
The results, as regards B. enteritidis sporogenes, are given in the following table—

The sign 4- signifies the presence and the sign — the absence of the spores of B. enteritidis
sporogenes.
These results are shown in graphic form in Diagram 8.
It is to be noted that although the number of spores of B. enteritidis sporogenes was
frequently less in the effluents from the 13-feet coke-bed than in the corresponding samples of
crude sewage, the actual number of spores remaining in the effluent after the bacterial treatment
of the sewage was very large—usually at least 100, but less than 1,000 in 1 c.c.
(d) Number of Bacteria capable of growing in Agar at 37° C.
In the Second Report (page 27) it was pointed out that—"In experiments 3 and 5 (col. 5,
Table I.) the number of bacteria in the crude sewage capable of growing at 37° C. in agar was
estimated. The numbers were 1,260,000 and 1,171,000 per c.c., as compared with 3,670,000 and
6,400,000 obtained by gelatine plate cultivation at 20° C. A similar experiment (experiment 4)
with the effluent from the 4-foot coke-bed gave 1,630,000 (agar at 37° C.) as compared with
4,100,000 (gelatine at 20° C.) bacteria per c.c."
At the period (May, 1898) when these experiments were carried out the pressure of other
important work prevented a series of experiments being carried out on the above lines. It,
however, was considered important to extend these observations at as early a date as possible.