Contamination of Milk. 49 



amount of dirt and filth with which it has come in contact 

 since it was drawn from the cow. Bacteria and filth of all 

 kinds are so intimately associated with each other that the 

 presence of one rightly presupposes that of the other. 



As to the numerical content of any milk, there is such 

 a wide variation under different conditions that figures are 

 not of much worth unless surrounding conditions are 

 considered. No exact relation can be maintained between 

 the number of bacteria in milk and the development of 

 fermentative products. 



Under American conditions data are gradually being 

 accumulated, but the subject has not been exhaustively 

 studied. Milk in this country as it reaches the consumer 

 usually contains fewer bacteria than are to be found in 

 European supplies, although as Conn has pointed out, it is 

 often older. As he intimates this is explained by the rela- 

 tively free use of ice in this country. A few determina- 

 tions of the bacterial content of European milks that 

 have been analyzed biologically will illustrate this point. 



Renk 1 found in Halle milk supply 6 to 30,000,000 germs 

 per cc.; Cnopf 2 in Munich milk supply 200,000 to 6,000,000 

 per cc.; Uhl 8 in Giessen milk 83,000 to 170,000,000 per cc.; 

 Clauss 4 in Wurzburg 222,000 to 23,000,000 per cc.; Bujwid 

 in Warsaw an average of 4,000,000 per cc., and Knochen- 

 steirn 5 in Dorpat 25,000,000 per cc. 



Sedgwick and Batchelder 6 report fifty-seven samples of 

 Boston milk as containing from 30,000 to 4,220,000 per cc. 

 In the country, they found in the milk fresh from the cow 



J Renk, Cent. f. Bakt. 10:193. 

 8 Cnopf, Ibid. 6: 553. 

 Uhl, Zeit. f. Hyg., 1892, 12:475. 

 4 Clauss, Diss. Wurzburg, 1889. 



* Knochensteirn, Chem. Cent., 11:62. 



Sedgwick and Batchelder, Boston Med. Surg. Journ., Jan. 14, 1892. 



4 



