Investigate by question and inspection, if possible, the available milk supply. Be sure to do this in the country in the summer. Always buy bottled milk. Where the income is small, good quality milk should be used for the little children and invalids, and skim milk purchased for cooking. In many places skim milk is supplied in bottles by reliable firms. The usual price for bottled milk in the city is 8 to 10 cents, and this is of good average quality. Keep milk cold. If there is no ice, use an ice substitute (page 74), and in very hot weather pasteurize or scald the milk, cooling afterward as quickly as possible by placing in cold water and stirring the water.