CHURNING AND WASHING BUTTER. 



249 



seasons of the year. In the spring, when rains are frequent 

 and heavy, unwholesome surface-water is likely to seep in 

 through the sides. Such wells may also serve as traps for 

 small animals. The presence of an animal in the well is sure 



Fig. 151. — The shallow barnyard well with privy- vault and manure heaps 

 near by. The water is Hkely to be contaminated from these any time. 

 (Farmer's Bui. No. 43, U. S. Dept. of Agriculture.) 



to cause undesirable odors and a multitude of undesirable and 

 putrefactive organisms. 



Water from deeply drilled wells, even if it is pure in so far 

 as its germ-content is concerned, is in many cases turbid and 

 sandy, and needs to go through a process of purification as nmch 

 as does the shallow well-water. 



