[ 56 ] 
elsewhere. In all probability the only method in which Typhoid infection 
occurs here amongst Europeans is from water. The main water supply 0 f 
the town is drawn from an area free from human habitation andlLidlv 
reserved. Fcecal contamination with Typhoid dejecta is almost impossible^ 
The town service reservoir is on an isolated hill, has no houses ablve i is 
well covered in, and free from any possible source of contammatml 
ere is no leason to suspect contamination of the water during delivery 
Unfortunately considerable areas in and close to the town are not supplied 
cJsIssimlmd ^‘I® n at?r US6d ' S d . erived from wells and pits in many 
become infected nS con “ ated b 7 sewage and so may easily 
bbe areas not supplied by town water include all the larger cattle 
stations. \\ ater derived from any source is freely used either for” washing 
utensils or for diluting the milk, and it is to this milk that the cases of 
drinP° ld occurrm ? amongst Europeans who use town water only for 
bifore use PUrP ° SeS 15 pr ° bably t0 be attributed > as it is often not boiled 
Wn The ’?- IS llttle llkellh °° d of the disease being either dust born or fly 
snip f T count [y ail ; on gst Europeans. Except on the roads in Ion- 
spells of dry weather there is little dust and flies occur only in small 
numbers in well kept houses. y 
Y\ 1th the Chinese the conditions differ greatly. Town water is not 
supplied to all parts and surface wells are freely used. Very little unboiled 
wa1hW S ,,m ed l by th 1 u, hmeSe for drinkin g purposes, bin it is used for 
hon the m? wded P arts of the town dust is present in abundance in 
houses gambling farms, theatres, etc. Examination of samples of dust 
resulted^ filH OUS P la “ s ° f P ubhc resort > fr om lodging houses and brothels, 
resulted in finding B. Coll communis in 66% of the samples taken. Even 
\ vfct ,'y eathc j r the dust m these places is abundant and easily 
t T U f e .' . ast ’ therefore, cannot be excluded from amongst the sources 
ot intestinal disease amongst the Chinese. 
In some of the Chinese houses flies, Mnsea domestira, and several species 
ot Eucilia and Sarcophagi are abundant. The Chinese methods of disposal 
of excreta is probably ultimately destructive to pathogenic organisms, but 
L m ar y Stages of tb . e P rocess before this destruction has taken place 
these hies may convey disease. 
There is no evidence that the larva of these flies bred in the excreta 
harbour as imagines the human intestinal bacteria. As far as experi¬ 
mental work has gone even B. Coli communis does not seem to be carried 
in this maner. 
In the country districts the water supply is often inferior. Any stream 
or river passing through a mining district is always contaminated with 
excrement. Such water can usually be recognised at once, as much of the 
washings from a mine consist of finely divided white clay which remains in 
suspension in the water for prolonged periods. 
Surface wells are usually contaminated. It is common to find such 
wells in the immediate vicinity of drains, cesspits, and houses even in 
moderate sized towns or in Government institutions. It does not seem to 
be sufficiently realised that the area from which a surface well draws its 
water is considerably greater than a circle three or four times the depth of 
the well in diameter. v 
