PRACTICAL 7>/>7\ //:< 77" .Y \\I> > Tl:, .'//.//. 1 TION 133 



the milk be kept on ice. Unclean vessels hasten this process. No matter 

 how good milk may be in the morning, when comparatively fresh, 

 toward evening, unless it has been partly or completely sterilized, it 

 may be dangerous to an infant, and may, especially in summer, cause 

 fatal illness, even though it still tastes sweet. 



Complete sterilization destroys all the germs in milk, and so prevents 

 permanently fermentative changes. By partial sterilization most of 

 the germs which are not in the spore form may be destroyed, so that 

 the milk will remain wholesome for at least twenty-four hours in the 

 warmest weather. 



Milk is best sterilized by heat, for nearly all chemicals, such as 

 boric acid, salicylic acid, and formalin, are not only slightly deleterious 

 themselves but also make the milk less digestible, and, therefore, less 

 fit for food. It may be sterilized at a high or low temperature that 

 is, at the boiling temperature or at a lower degree of heat, obtained 

 by modifying the steaming process. 



It has been found that milk sterilized at a high temperature (100 C.) 

 is not desirable for prolonged use, as the high temperature causes cer- 

 tain changes in the milk which make it less suitable as a food for infants. 

 These changes are almost altogether avoided if a temperature below 

 80 C. is used. It is recommended, therefore, that the lowest tempera- 

 ture be used for partial sterilization which will keep the milk whole- 

 some for twenty-four hours in the warmest weather and kill the tuber- 

 cle, typhoid, and other non-spore-bearing bacilli. Raising the milk 

 to a temperature of 70 C. for fifteen minutes or 80 C. for twelve 

 minutes will accomplish this. One of the many forms of apparatus is 

 the following: 



(a) A tin pail or pot, about ten inches deep by nine inches in diame- 

 ter, provided with the ordinary tin cover which has been perforated 

 with eight holes each an inch in diameter. 



(6) A wire basket, with eight nursing bottles (as sold for this 

 purpose in the shops). 



(c) Rubber corks for the bottles and a bristle brush for cleaning 

 them. 



Directions (Koplik). Place the milk, pure or diluted (as the 

 physician may direct), in the nursing bottles and place the latter 

 in the wire basket. Put only sufficient milk for one nursing in each 

 bottle. Do not cork the bottles at first. 



Having previously poured about two inches of water in the tin pail 

 or pot and brought it to the boiling point, lower the basket of nursing 

 bottles slowly into the pot. Do not allow the bottles to touch the water 

 or they will crack. Put on the perforated cover and let the steaming 

 continue for ten minutes; then remove the cover and firmly cork each 

 bottle. After replacing the cover, allow the steaming to continue for 

 fifteen minutes. The steam must be allowed to escape freely or the 

 temperature will rise too high. 



The process is now completed. Place the basket of bottles in a 

 cool, dark place or in an ice-chest. The bottles must not be opened 



