In a previous paper1 we gave a rule for finding the percentage of total protein in milk from the percentage of casein. As printed it reads: "The percentage of casein multiplied by 1.4 will give the percentage of total protein..." This is incorrect and should read: "The percentage of casein multiplied by 1¼ will give the percentage of total protein..."
This rule is based on the figures given in the accompanying table:
We also wish to call attention to the fact that the approximate composition of milk may be found by a few simple calculations from the lactometer reading and the percentage of fat as determined by the Babcock method. The rules for these calculations are as follows:
1. Total solids:
L/4 + (1.2 × F) = total solids.
2. Solids not fat:
L/4 + (0.2 × F) = solids not fat.
(F − 3) × 0.4 + 2.1= per cent. of