THK WATER-SUPPLY OF TOWNS IN THE TKOl'IUS 295 



Following this, a systematic analysis of the water of a shallow well at the King 

 Institute was undertaken. By a shallow well, Major Glemesha means one which does 

 not pass through an impermeable stratum of soil or rock and is thus liable to contamination 

 from surface and soil washings. It was found that : — 



"1. In common with most other water-supplies, including rivers, lakes, springs, etc., 

 bacillus doacie would appear to be the predominating organism in a well after prolonged 

 drought. 



" 2. Even a small downpour of rain, after a prolonged spell of dry weather, has a systematic 

 very marked influence in increasing the number of ftecal bacilli in wells situated in ^'"dyufa 



■' ° " shallow 



porous soils. well" 



" 3. That early showers, following on a long period of hot weather, have caused an 

 increase in the number of coli communis in the well of the King Institute. Further 

 investigation is necessary before it can be stated that this is true of all wells. It is not 

 by any means certain where these coli communis come from, but it is unlikely that they 

 come from the surface of the ground, and probable that they remained alive in the 

 lower layers of the soil. 



"4. That after heavy downpours of rain, in consequence of which it is certain that 

 surface contamination has penetrated deep into the layers of soil, a mixture of ftecal 

 organisms is usually found in the water obtained from wells. Coli communis appear to 

 be present after early rains, but disappear as the rains become more plentiful. 



"5. Plentiful rains improve the quality of sub-soil water after the contaminated 

 surface water has run off the land. 



"6. Shallow wells are a most unsatisfactory source of water-supply, especially if 

 they are situated in a highly porous soil, and unless the greatest possible care is exercised 

 in protecting a large space of ground in the immediate vicinity from all chances of pollution." 



Thereafter, the bacteriological flora of the fseces of man and other animals were 

 studied and the following conclusions reached : — 



"1. That, the flora of the intestinal tracts of men and animals are subject to very 

 considerable changes due to influences which are at present unknown. These influences 

 have been proved to operate over very wide areas. 



" 2. That, within certain very wide limits, these forces appear to affect man and animals 

 equally, both as regards number and kind of micro-organisms. 



"3. That, under well defined conditions, such as heavy rainfall, the water-supplies 



^^ t.tcal bat-teiia 



contain the same organisms as the fsBces of man and animals at that particular time ; of men 

 but that this similarity of bacteriological flora is also noticed occasionally when rain is ^"'^ animals 

 absent, and there is no apparent cause for it. The explanation of this occurrence is at 

 present unknown. 



" -i. That, having regard to the variation in the bacteria in fteces, both in quantity 

 and kind, no constant approximate composition can be arrived at. Even in the large 

 groups, suggested by MacConkey, variation in percentage composition in the same animal 

 is considerable. 



"5. No lactose-fermenting organism has been isolated by us that has been proved to 

 be the inhabitant of the intestinal tract of cattle or man only. 



" 6. That the numerical relation of the organisms constituting MacConkey's groups 

 in the intestines of cattle in India is entirely different from that in England : while in 

 the intestines of man it appears to be very similar in the two countries. 



" 7. That a study of the organisms present in faeces at different times of the year 

 is necessary for the proper interpretation of the results obtained from water analyses." 



