CuF .290 × 51.2 ----- = ------------- = 4.56 the true per cent of invert sugar. W 3.256 MEISSL AND HILLER’S FACTORS FOR THE DETERMINATION OF MORE THAN ONE PER CENT OF INVERT SUGAR. Ratio of Approximate absolute weight of invert sugar = _Z_. sucrose I = I = I = I = I = I = I = to invert 200 175 150 125 100 75 50 sugar = mg. mg. mg. mg. mg. mg. mg. R : I. 0 : 100 56.4 55.4 54.5 53.8 53.2 53.0 53.0 10 : 90 56.3 55.3 54.4 53.8 53.2 52.9 52.9 20 : 80 56.2 55.2 54.3 53.7 53.2 52.7 52.7 30 : 70 56.1 55.1 54.2 53.7 53.2 52.6 52.6 40 : 60 55.9 55.0 54.1 53.6 53.1 52.5 52.4 50 : 50 55.7 54.9 54.0 53.5 53.1 52.3 52.2 60 : 40 55.6 54.7 53.8 53.2 52.8 52.1 51.9 70 : 30 55.5 54.5 53.5 52.9 52.5 51.9 51.6 80 : 20 55.4 54.3 53.3 52.7 52.2 51.7 51.3 90 : 10 54.6 53.6 53.1 52.6 52.1 51.6 51.2 91 : 9 54.1 53.6 52.6 52.1 51.6 51.2 50.7 92 : 8 53.6 53.1 52.1 51.6 51.2 50.7 50.3 93 : 7 53.6 53.1 52.1 51.2 50.7 50.3 49.8 94 : 6 53.1 52.6 51.6 50.7 50.3 49.8 48.9 95 : 5 52.6 52.1 51.2 50.3 49.4 48.9 48.5 96 : 4 52.1 51.2 50.7 49.8 48.9 47.7 46.9 97 : 3 50.7 50.3 49.8 48.9 47.7 46.2 45.1 98 : 2 49.9 48.9 48.5 47.3 45.8 43.3 40.0 99 : 1 47.7 47.3 46.5 45.1 43.3 41.2 38.1 =143. Table for the Estimation of Milk Sugar.=—The solutions to be used for this table are the same as those employed in the preceding table for the estimation of invert sugar. The milk sugar is supposed to be in a pure form in solution before beginning the analysis. The method to be employed for milk will be given in the part devoted to dairy products. In the conduct of the work twenty-five cubic centimeters of the copper solution are mixed with an equal quantity of the alkaline tartrate mixture, and from twenty to one hundred cubic centimeters of the sugar solution added, according to its concentration. This solution should not contain less than seventy nor more than 306 milligrams of lactose. The volume is completed to 150 cubic centimeters with boiling water and kept in lively ebullition for six minutes. The rest of the operation is conducted in the manner already described. From the weight of copper obtained the quantity of milk sugar is determined by inspecting the table. It is recommended to use such a weight of milk sugar as will give about 200 milligrams of copper. TABLE FOR DETERMINING MILK SUGAR.