22 DOMESTIC WATER SUPPLIES FOR THE FARM 



means of chemical examination; but waters contain so many 

 harmless substances dissolved from the earth that the determina- 

 tions by a chemist are often inconclusive. Careful observation of 

 the spring itself and a common-sense inspection of its surround- 

 ings are usually of more value than an analysis. The spring 

 should be protected from pollution, especially from surface drain- 

 age from houses, barns, hogpens and other outhouses that are 

 situated on the slopes above it within a distance of several hundred 

 feet. When the absence of such local sources of pollution is es- 

 tablished the water should be carefully watched, especially in 

 limestone regions, for muddiness or floating matter rising with the 

 water after severe rains. Such phenomena are evidence of con- 

 nection with sink holes and indicate that the water is to be looked 

 upon with grave suspicion if opportunity exists anywhere within 

 miles for the entrance of polluting matter through sinks or other- 

 wise. Figure 9 shows a spring in Greene County, Missouri, used 

 for dairy purposes. The spring is remote from buildings and the 

 water is clear, cold and sparkling, but is, nevertheless, more or 

 less polluted, owing to the fact that the underground stream feed- 

 ing the spring appears at the surface at a number of points above 

 it, crossing one or more highways and receiving the drainage from 

 them and from a cemetery. 



Protection of Springs. One of the most common causes of 

 contamination of springs in the farming districts arises from fail- 

 ure to fence the springs to prevent the access of stock. Figure 10 

 shows a mineral spring in Georgia from which many people drink 

 and from which the waters have at times been shipped, but about 

 which stock are nevertheless allowed to roam freely, drinking 

 from it at will and incidentally contaminating it in a variety of 

 ways. It is needless to say that any spring used for drinking 

 water should be carefully fenced at such a distance as to prevent 

 any excrement from reaching it. 



The spring mentioned above is located only a few inches above 

 the bottom of the stream channel shown on the right of the view. 

 When the picture was taken no water was flowing in the channel, 



