Clarification of the Public Water Supply of Cincinnati. 3 1 



Ferric Chloride. (Series 12.) 



150 to 200 parts by weight of Ferric Chloride Solution, Sp.G. 

 1.74 will clarify 1,000,000 parts by weight of Hydrant Water in 

 from 24 to 48 hours with an increase in hardness of from yi to 2 

 Metric degrees. 



Series 16. 



200 to 250 parts are required of solution, Sp. G. 1.31 and the 

 increase in hardness is from i to 3 degrees. 



The weaker the solution the greater the hardness imparted. 



Ferric Fer Sulphate. (Series 15.) 



200 to 300 parts by weight of solution of Ferric Fer Sulphate 

 Sp. G. 1.3 1 will clarify 1,000,000 parts by weight of Hydrant 

 Water with an increase of hardness of from 2 to 5 Metric degrees. 



Ferric Sub-sulphate. (Series 2 & 14.) 



150 to 250 parts by weight of Ferric Sub-sulphate will clarify 

 1,000,000 parts by weight of Hydrant Water in from 24 to 48 

 hours with an increase in hardness of from i to 3 Metric degrees. 



Canal Water. (Series i.) 



100 to 200 parts by weight of Per-chloride of Iron Solution, 

 Specific Gravity 1.74 will clarify 1,000,000 parts by weight of 

 Canal Water in 24 to 48 hours with an increase in hardness of 2 to 

 3 Metric degrees. 



The clarified water will contain less Iron than the turbid canal 

 water. It will be sparkling and bright and have a degree of hard- 

 ness of from 38 to 40 Metric degrees. 



It can not be used for drinking or culinary purposes, but would 

 be available for general cleansing purposes, such as street sprink- 

 ling, washing pavements and flushing gutters. If used for cleans- 

 ing with the help of soap, it should be softened when clarified ; 

 otherwise it would destroy four times as much soap as the river 

 water. 



Effect of the Iron Salts on the Clarified Water. 



(Series 14, 15 and i.) 

 The turbid water clarified by the minimum quantity of Iron 

 Salts necessary, contained less Iron than was in it before treatment. 



