128 



MICRO-ORGANISMS IN WATER 



The close proximity of tlie intakes of the five Thames 

 companies, however, furnishes a favourable opportunity 

 for instituting a qomparison. 



' The factors in the mode of working, which have 

 been pointed out as of special importance in exercising 

 an influence on the result obtained are given in the 

 following table, the figures being taken from the statis- 

 tical table given in Sir F. Bolton's "London "Water 

 Supply'" 1884:— 



More important Factors in mode of Treatment by Thames 

 Water Companies 



' By means of this table the five companies may now 

 be classified with respect to each of the four factors in 

 question, thus : — 



' From this, the general order of merit, as regards 

 these factors, can be deduced, by taking the average 

 position of each company, thus : — 



