Report on the Bacteriology of Water. 



465 



These results, therefore, entirely confirm those previously obtained, 

 the disappearance of both the typhoid and coli bacilli being even still 

 more rapid than on the former occasion. 



Results of a similar character were also subsequently obtained with 

 t)ther waters sterilised by filtration (see pp. 479, 483, 502), in seme 

 of which, moreover, totally different filters, constructed of infusorial 

 earth, were employed. 



SECOND SERIES OF EXPERIMENTS. 



The Behaviour of the Typhoid Bacillus and of the B. coli communis in 

 Loch Katrine Water. 



Having, in the first series of experiments, determined the behaviour 

 of these bacilli in a typical calcareous surface water like that of the 

 Thames, which receives the drainage from cultivated land, I pro- 

 ceeded in the next instance to carry out a somewhat similar series o 

 experiments with Loch Katrine water, which may be taken as a type 

 of an upland surface water derived almost exclusively from unculti- 

 vated land, and of a somewhat peaty character. 



The sample of Loch Katrine was collected from a tap on the main 

 in the Broomielaw, Glasgow, on Jue 30th, 1893. 



Submitted to plate cultivation on the spot, it was found to contain 

 , 112 bacteria in 1 c.c., whilst on chemical analysis it yielded the 

 following figures : 



