24 MODERN DAIRY PRACTICE. 



show the original sterility of milk after the experience 

 gathered by the above-given scientists. It is, however, 

 necessary strictly to observe certain precautions. The 

 udder and its environments must be carefully cleaned with 

 soap and water, treated with corrosive sublimate solution 

 and washed with boiled, rapidly cooled water. The milk- 

 er's hands should be washed in ether and alcohol, then 

 rinsed with sublimate solution, and carefully washed in 

 boiled water. ' The milk is drawn into sterilized glass 

 vessels. Good results are generally secured when these 

 precautions are followed, and when the milking is done 

 rapidly and with precision, preferably at some place away 

 from the cow-stable and other places filled with micro- 

 organisms.* 



* The difficulty which bacteriologists have often found in obtain- 

 ing absolutely sterile milk, when it has been drawn under observa- 

 tion of all possible precautions, is explained by the observation made 

 by Lehmann, that bacteria found in the drop of milk at the opening 

 of the teat are able to work their way into the milk-cistern, where 

 they then multiply very rapidly, favored both by the high tempera- 

 ture and the rich nutritive medium. At milking the bacteria in the 

 milk-cistern will be largely washed out in the first portions of milk 

 drawn, but all are not removed until the milking has progressed for 

 some time. Lehmann (17fe Versammlung d. deut. Ver. f. offent. 

 Oesundheiispflege) thus found that the first milk drawn (300 cubic 

 centimeters, about 10 oz.) contained 50,000 to 100,000 bacteria per 

 cubic centimeter, while the main quantity of the milk drawn con- 

 tained 5000 bacteria per cc. on an average, and the last 300 cc. were 

 almost or entirely free from bacteria. Schulz (Arch. f. Hyg. t 14, 260) 

 in the same way showed that the first portion of a milking contains 

 a large number of bacteria, while the last portions of milk are sterile 

 when proper precautions have been taken. See also Gernhardt, 

 Quant. Spaltpilzunters. d. Milch, Inaug. Dissert. Univ. Jurjew, 

 1893. W. 



