DISEASES OF CATTLE 55 



course. (Report upon Hog Cholera, Bureau of Animal Industry, 

 1889, p. 124.) 



Some conception of the number of germs that are present in 

 water and the filtering property of the soil may be obtained from the 

 following. The quantity in each case is one cubic centimeter, or a 

 half thimble full. 



Number of germs per 

 Source. cubic centimeter. 



Very filthy hog wallow 2,680,000 



Ordinary hog wallow 730,000 1,420,000 



Wabash river above LaFayette 12,000 32,000 



Wabash river below LaFayette 112,000 390,000 



Clean looking pond 290,000 



Filthy watering trough 248,000 



Stock troughs 5,000 21,000 



Tile drains 8,000 



Six cisterns, without filters 5,000 91,000 



Four cisterns, with filters 580 3,000 



Dug well receiving surface drainage 420,000 

 Dug well 14 feet deep in corner of 



unprotected barn lot ,. . 398,000 



Eight tubular wells 60 to 150 feet 



deep 4 16 



A test upon the filtering properties of the soil is as follows : 



Number of germs after 



Depth. Number of germs. a heavy rain. 



Surface 518,400 312,000 



1 inch 51,200 



2 " 28,800 



3 " 17,600 



4 " 17,600 



5 " 13,600 



6 " 13,200 47,500 

 8 " 8,000 



10 " 12,800 



12 " 5,200 16,000 



18 " 10,400 



24 " 2,000 6,000 



30 " 3,600 



36 " 4,000 4,300 



42 " 3,600 



48 " 3,000 3,100 



54 " 2,800 



The bacteria ordinarily found in water are not injurious, but 

 the number present may always be taken as an index of its unwhole- 

 someness. A larger number indicates that it is easy for contamina- 

 tion to occur, while a smaller number may be accepted as an evidence 

 of difficulty for extraneous germs to find entrance. 



If the larger streams have such a marked influence upon the 

 percentage of loss along their courses, it is only reasonable to suppose 



