52 



CHEMISTRY OF FARM PRACTICE 



attractiveness of the water may be considered. These are 

 taste, odor, color, turbidity, and sediment. The desirability 

 of a good source and supply of water cannot be urged 

 too strongly on the rural householder. It is an economic 

 proposition, saving large sums in expense incident to sick- 

 ness, and even more through increased efficiency. No man 

 can work to best advantage when handicapped by poor 



FIG. 16. Flowing well near Conway, S. C. (Photo by Prof. C. E. 



Chambliss.) 



health, which in many .cases is the direct result of a poor 

 water-supply. 



44. Hardness in Water. Hardness in water is caused 

 by the presence of metallic salts, usually those of calcium 

 or magnesium, dissolved in the water. When soap is 

 added to such waters, the fatty acid radicals of the soap 

 combine with the calcium and magnesium and produce 

 an insoluble curdy precipitate. Until "all of these calcium 

 and magnesium salts are thus precipitated, no lather can 



