APPLICATION OF LIQUID CHLORINE 3393 
ilization. Experiments on the raw Thames river water showed that 
B. coli were killed in from 5 to 24 hours in a concentration of 1 to 5000. 
Hoover and Scott (1914) claim that if enough lime is added to the water 
to absorb the free and half-bound carbonic acid and the precipitate the 
magnesium, B. colon and B. typhi are killed in 48 hours after being so 
Fic. 62.—Automatic Control Chlorinator Direct Feed. (Wallace-Tiernan Co.) 
treated, if the water does not contain large quantities of organic matter. 
An effective bactericidal action when the lime was added in from $ to 
1 part per million in excess of that which is needed to reduce the tem- 
porary hardness. Intestinal bacteria will not live in a water containing 
no free or half-bound carbonic acid. When a lime-softened water is 
inoculated with typhoid bacteria or crude sewage, it soon becomes bac- 
