1889-90.] NATUKAL HISTORY OF GROUND WATERS. 167 



Other waters which were examined. The water samples were taken 

 under the supervision of Dr. N. H. Beemer of the medical staff of the 

 asylum in sterilized and capped tubes sent to him from week to week. 

 The examinations made the succeeding day, while not giving the exact 

 number of the microbes in the water at the time of taking, would yet give 

 the comparative results of the different species and the results of the 

 different week's examination of the few drops of water taken from any 

 water, this being all that is needed for an examination. I may say that 

 the successive samples of different waters showed surprising constancy 

 of forms, both as regards species and number. For instance : — 



No. I. Tile drain, 14 forms — 10 liquefying, 4 non-liquefying. 



No. 2. Effluent from sewage farm, 6 liquefying, 3 non-liquefying. 



One week only. 



No. 3. East creek. All portions of culture showing innumerable slowly 

 liquefying spots, all the same form apparently ; probably M. candicans. 



No. 4. Carling's Creek. All portions of the gelatine show innumerable 

 liquefying points with whitish granular particles in the larger liquefac- 

 tions. 



Nos. 5, 6, 7 were practically sterile, showing as they did only one or 

 two forms which were not moulds — possibly got from the air of the tank 

 rooms. I shall say nothing more regarding their species, except that they 

 were few in number, some seven in all in the whole series of cultures. The 

 notable fact gained was, however the innumerable bacteria present in the 

 open water of creeks. Samples taken again and again from both Carl- 

 ing's creek and East creek always produced one form in great abundance 

 — probably M. candicans — in the latter in greater abundance as the 

 water with the drought became less and more impure. It was always 

 with much satisfaction that our inoculations of London city water indi- 

 cated practical sterility, taken as it is from springs appearing at some 

 height above the river bank below the city and gathered in a small collect- 

 ing gallery. The samples were taken from a city tap. The same sterility 

 was found in the water coming from a faucet in the pump-house at the 

 asylum, the water coming from a bored well of considerable depth. The 

 water from the tank at the top of the building showed occasionally a mould 

 or two as would be expected from a tank in a confined space at the top of 

 the house. No less interesting is the fact that the water arriving at the 

 mouth of the tile yielding sub-surface drainage from a field was practi- 

 cally free from bacteria. The effluent water from the tile drain leading 

 from the sewage farm, the one week that a sample could be obtained) 

 showed as e^reat freedom from contamination as did the other tile water- 



