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The daily quantity of the milk drawn from the breast by the child 
is best determined by weighing the child before and immediately 
after each feeding during the entire twenty-four hours for several 
days. An accurate set of scales, sensitive to 15 grams (J ounce) should 
be used. By computing the sum of the weights of the separate feed- 
ings for each day and striking an average for the daily amounts 
during the period of observation, the average amount of the daily 
consumption of milk can then be determined. As children vary in 
age, weight, and nutritive needs, the figures obtained will only be of 
value when compared to the body weight and age of the child that 
received them, as is subsequently to be discussed. 
Reaction . — This may be tested by litmus paper and should be 
alkaline or amphoteric, never acid. 
Specific gravity. — This may be determined with the aid of any 
small hydrometer, such as a urinometer with a scale registering from 
1,010 to 1,040. The specific gravity is lowered by fat, but increased 
by the other solids. 
Microscopical examination. — Besides the fat globules, the micro- 
scope may reveal the presence of colostrum corpuscles, blood, pus, 
epithelial cells, bacteria, and granular detritus. The presence of colos- 
trum corpuscles is abnormal after the twelfth day of lactation. Blood 
and pus are always abnormal. The presence of blood and pus in the 
milk require the suspension of lactation until they disappear. 
Determination of fat. — The simplest method of determining the fat 
of woman’s milk is by Holt’s cream gauge. This is a graduated tube 
on a foot, with a glass stopper. The tube is filled with freshly drawn 
milk to the zero mark at the top of the scale and the whole allowed 
to stand at room temperature for twenty-four hours. The percentage 
of cream according to the scale is then read off. The ratio of the 
cream to the fat content is as 5 : 3 ; e. g., 5 per cent of cream equals 3 
per cent of fat, etc. 
While not very accurate, this method suffices for clinical purposes. 
Results approximating the accuracy of a chemical analysis may be 
obtained by the Babcock test or by Lewis’s modification of the Leff- 
man and Beam test for cow’s milk (Holt). This is a centrifugal test 
for which special tubes are required, which, however, may be used in 
the ordinary centrifuge for urine. 
Sugar. — The percentage of sugar in human milk is subject to very 
little variation, and may be regarded as constant for clinical pur- 
poses. 
Proteids . — The determination of the proteids in woman’s milk is an 
elaborate process requiring the resources of a well-equipped chemical 
laboratory. 
We may, however (according to Holt), gain an approximate idea 
of their percentage by considering the sugar and salts of milk as con- 
