DRINKING WATER SUPPLIES: 
A Chemical and Bacteriological Study of the Drinking Water Supplies 
on Estates from a Hygienie Point of View. 
By 
Kess Wise MEBs BS!) BSc: “D:P!H.. 
Government Medical Officer of Health and Bacteriologist, 
and 
Ey PY Moyers, M.D: DP DIM. & H., 
Assistant Government Medical Officer of Health and Bacteriologist. 
When first directed to begin this investigation it was with consider- 
able trepidation that the commission was received; especially as our 
colleague, Professor Harrison, was, owing to pressure of work unable to 
co-operate with us by carrying out the chemical analyses. This meant 
that both bacteriological and chemical analyses had to be carried out 
in the laboratory, Public Hospital, Georgetown, by one of us, a very 
considerable amount of extra work. It was therefore decided to spread the 
investigation over a longer period than was originally intended. 
The scheme briefly was as follows :—By taking a large number of 
samples of water and carrying out a complete bacteriological and chemical 
analysis in each case, a set of results would be obtained from which it 
would be possible to form an opinion as to the hygienic value of the 
water supplies and to arrive at an approximate standard of purity for 
future guidance. In order to negative climatic and local influences as 
much as possible samples were taken both during the dry and wet 
seasons, especially after heavy rains, in order to demonstrate the 
possibility or otherwise of surface contamination due to improper con- 
servation of the supplies. An enormous number of investigations were 
carried out and embodied with full detail in a departmental report for 
Government consideration. As this is the first attempt to make a com- 
plete bacteriological and chemical survey of the estates’ water supplies 
of the colony, no efforts were spared to ensure the accuracy of results in 
order that a reasonable standard might be available for future investiga- 
tions. 
The scheme adopted was based on the following essentials acknow- 
ledged by all water experts as the irreducible minimum :— 
1. A careful topographical survey at the time of collection together 
with a rough sketch made on the spot available for future 
reference. 
2. A bacteriological examination carried out as soon as_ possible 
(frequently within an hour, rarely later than 3 or 4 hours) after 
collection. 
3. A chemical analysis carried out on the same day as the sample was 
collected, 
