456 



EEPOKT 1893. 



1886. — Nmnher of Micro-organisms in 1 ex. of River Thames Water before 



and after Filtration. (Percy Frankland.)' 



Description of Water. 



1886. — Percentage Reduction in the Number of Micro-organisms present in 



the River Waters before delivery by the Companies. 



Description op Water. 



In the following table are recorded the results obtained in two 

 experiments, made in 1885, on the softening of water by Clark's process 

 on the large scale : — 



Number of Micro-organisms in 1 c.c. of Water. (Percy Feankland.) 



Unsoftened deep well water obtained from chalk .... 322 

 Unsoftened deep well water obtained from clialk after softening 



by Clark's process 4 



Keduction = 99 per cent. 

 Unsoftened deep well water obtained from chalk . . . .182 

 Unsoftened deep well water obtained from chalk after softening 4 



Reduction = 98 per cent. 



The following table exhibits the remarkable manner in which bacteria 



' Taken from the monthly reports presented to the Local Government Board for 

 the year 1886. 



i 



