132 THOMPSON YATES LABORATORIES REPORT 
supplying the hospital, on October 30.' This sample contained the spores of 
bacillus enteritidis, and the cultures were virulent to guinea-pigs. ' Inquiry into the 
source of the milk of the company which supplied it, elicited the facts that on Sunday, 
October 27, seventeen gallons out ol a total of 190 gallons came from a certain farm 
at Melton Mowbray, and the sample furnished on October 30 was from the same 
farm.' Dr. Andrewes also remarks, ' that on the supposition that the milk was the 
cause of the diarrhoea outbreak, the irregular and capricious distribution of the disease 
in the hospital need excite no surprise, for the manner in which the milk was sent 
out to the different wards would well explain it. It was poured through a strainer 
into a wooden tub, from which the ward vessels were filled, and this tub was never 
allowed to get empty, but a fresh churn was poured into it when it got low, thus 
leading to an irregular mixture of the milk from one churn with that of the others.'* 
It was concluded from these observations that the outbreak in question 
'appeared referable 'f to the bacillus enteritidis sporogenes, 'a diarrhoeal organism. '| 
I have attempted to state as clearly as possible what seem to be the main 
reasons for this conclusion — 
(1) The spores of bacillus enteritidis were demonstrated in the evacua- 
tions of the persons attacked. 
(2) The outbreak was attributed to milk from a certain farm, and it was 
assumed, inasmuch as the spores of the bacillus enteritidis were 
detected in a sample of milk obtained from this farm three days 
after the outbreak, that they were also present in the original toxic 
milk. 
(3) The bacillus enteritidis was regarded as an ' uncommon ' organism, 
and had not been detected in the normal evacuations of healthy 
individuals. 
(4) The milk cultures obtained from the evacuations and from the 
hospital milk were pathogenic to guinea-pigs. 
It is curious that milk obtained from the Melton Mowbray farm ' was supplied 
both before and since the outbreak ' at St. Bartholomew's ' to other customers without 
producing any harmful effect, so far as the company's knowledge went.'§ 
At present B. enteritidis can only be detected in a given material by cultivating 
its spores, consequently if the bacillus is present in a non-sporing condition, the 
result of cultivation will be negative. However, as B. enteritidis very readily forms 
spores, their absence must be taken, in practice, to indicate the absence of the bacilli 
also. 
In order to isolate the spores from faeces, a small particle is inoculated into a 
tube of recently sterilised litmus milk, which is heated for fifteen minutes from 70°C. 
* Medical Officers Report, Local Government Board, for 1895-96, p. 198. 
I Medical Officer's Report, Local Government Board, for 1895-96, p. 197. 
% Medical Officer s Report, Local Government Board, for 1895-96, p. 204. 
§ Medical Officers Report, Local Government Board, for 1895-96, p. 198. 
