238 ELEMENTS OF WATER BACTERIOLOGY 



in the table below smaller amounts of chlorine than 

 were used by Rideal will give good results with more 

 dilute American sewages. 



BACTERIA IN TRICKLING FILTER EFFLUENT BEFORE 

 AND AFTER TREATMENT WITH CHLORIDE OF LIME 

 (5 PARTS PER MILLION AVAILABLE CHLORINE) 



(PHELPS AND CARPENTER, 1906) 



The success of chemical disinfection varies with the 

 character of the sewage or effluent treated, since the 

 organic matter present consumes a certain amount 

 of the disinfectant and renders it inoperative. Dis- 

 cordant results are therefore reported from different 

 sources. 



An important series of experiments tarried out in 

 Ohio by Kellerman, Pratt, and Kimberly (1907) 

 showed good results with sand filter effluents and 



