THE MICROBE OF MILK 89 



man, become fat and plump. It is because they 

 feed on the richest and best food in the world. 



Hence the production of milk is one of the great 

 industries of the world. The United States keeps 

 about 20,000,000 cows, one cow to every four 

 persons. At the rate of eight quarts of milk per 

 cow per day, the entire flow of milk would be equal 

 to a river of milk six feet deep, twenty-four feet 

 wide, and flowing perpetually at the rate of 240 

 feet every 24 hours. This river of milk in one way 

 or another, including butter and cheese, constitutes, 

 in some respects, the best and most essential part 

 of the food of more than 90,000,000 people. 



Surely the microbe of milk figures in human life 

 on a large scale. 



