resources of the world by conserving the excess of one season 



and one locality for use at other times and places. Skim 



milk is a highly valuable food material which should be sold 



freely if properly labeled. There are butter substitutes on 



the market which are as valuable for food as real butter 



and cost but half as much. 



The purity in foods is mainly a question p, •♦«■ h 



of honesty. Clean food, on the other hand, ~. .. 



u i +• i f \ uu Cleanliness 



is a vital essential of health. 



Polluted water in the past has been a common cause of 



disease both in the camp and in civil life. n - 



All surface water supplies, lakes and streams _. „ . , — T , 



.. ,. . n x. , t Polluted Water 



are liable to pollution from sewers or from 



material washed in from the banks, and wells and springs 

 may be polluted through crevices in the soil. No water 

 should ever be drunk if there is any uncertainty as to its 

 quality. The water for troops in the field should be purified 

 by filtration or disinfection, and it is one of the first duties 

 of the soldier to avoid the use of any unauthorized supplies. 

 Water of doubtful quality may be made safe by boiling or 

 bj' the addition of chloride of lime. Dissolve a teaspoonful 

 of chloride of lime in four pints of water and add one teaspoon- 

 ful of this solution to a gallon of the water to be purified 

 (one tablespoonful to four gallons, ten tablespoonfuls 

 to a barrel). The water should stand for half an hour 

 before use. 



Milk is another food which often carries the germs of 

 disease, germs of tuberculosis from the cow, n f 



or germs of typhoid fever, sore throat, M ..^ 

 diphtheria, etc., from human beings who 

 have handled it. Milk should always be pasteurized or 

 heated to 140 Q -145 C F. for 20 to 30 minutes before it is used, 

 and on no account should uncooked cow's milk be given to 

 young children. 



The best way to pasteurize milk in the home is to set the 

 bottles in a deep pan of water on the stove, put a milk 



13 



