136 THOMPSON YATES LABORATORIES REPORT 
Dr. Andrewes was led to this conclusion, among others, ' Whether the bacillus 
in question is actually a cause of acute diarrhoea is not so far positively established, 
but there seems to be a distinct probability that such is the case.'f 
There is, however, in my opinion, one striking feature in these experiments, 
i.e., the spores were apparently absent in five cases of acute sporadic diarrhoea, three 
being choleraic ; and present in two instances at least, in which the diarrhoea was 
merely looseness of the bowels without any acute symptoms. 
Professor Boyce suggested to me, during some observations on bacillus coli 
commune in diarrhoeal evacuations, that I should also ascertain whether the spores of 
bacillus enteritidis were present. Now, it was necessary for the isolation of bacillus 
coli, by means of agar plates, to use very dilute solutions of stool ; and it was these 
dilute solutions which were first tested for the spores of enteritidis, and consequently 
the quantity of stool examined was very minute. The dilution was the following : — 
One platinum loopful of faecal matter was well mixed with one cubic centimetre of 
sterile water, and as a rule from one to five loops of this solution were inoculated 
into litmus milk, subsequently heated for fifteen minutes from 70° C. up to 8o° C, and 
inoculated anaerobically. The size of the platinum loop used on different occasions 
was approximately the same, for it was made by using a piece of wire as a gauge. I 
have found by careful measurement that one cubic centimetre of water contains about 
thirteen hundred such loopfuls, and consequently a rough comparison of the dilution 
used may be obtained by adopting the following standards : — One loopful of a 
solution of one loopful of stool in one cubic centimetre of water represents a dilution 
of 1,300 ; while if five loopfuls are taken the dilution is 260 ; if half a cubic 
centimetre the dilution is two, &c. 
The samples of stools obtained from hospital patients were kindly provided 
in sterilised vessels by Dr. Hay and Dr. Fletcher. Unfortunately, I did not in 
many instances ask for a brief account of the disease with which the diarrhoea was 
associated ; but in no case was it the result of typhoid or of the action of 
drugs, and only one patient had distinct symptoms of enteritis. Often the diarrhoea 
was slight, the stools being semi-solid. 
The results of the examination of seventeen samples of evacuations from different 
individuals are classified below for the sake of brevity. In cases 1 to 1 1 the dilution 
represents the minimum dilution in which the spores were absent ; in the remainder 
the maximum dilution in which the spores were present. The whey of typical milk 
cultures only was inoculated subcutaneously into guinea-pigs in the proportion of 
1 c.c. to every 200 grms. of guinea-pig. If the animal died in about thirty hours or 
less, the virulence of the culture is described as ' normal ; ' if death occurred in two to 
four days it is diminished. If the animal recovered with sloughing of the skin at 
t Medical Officer, Report, Local Government Board, 1896-97, p. 260. 
