10 | 1.3 | 6.22 | 0.79 | 3.79 10½ | 1.36 | 6.53 | 0.83 | 3.97 11 | 1.43 | 6.84 | 0.87 | 4.16 11½ | 1.49 | 7.2 | 0.91 | 4.35 12 | 1.56 | 7.46 | 0.95 | 4.54 12½ | 1.62 | 7.78 | 0.99 | 4.73 13 | 1.69 | 8.09 | 1.02 | 4.92 13½ | 1.75 | 8.4 | 1.06 | 5.11 14 | 1.82 | 8.71 | 1.1 | 5.29 14½ | 1.88 | 9.02 | 1.14 | 5.49 15 | 1.94 | 9.33 | 1.18 | 5.67 15½ | 2.01 | 9.65 | 1.22 | 5.86 16 | 2.07 | 9.94 | 1.26 | 6.06 16½ | 2.14 | 10.27 | 1.3 | 6.24 17 | 2.2 | 10.51 | 1.34 | 6.43 17½ | 2.27 | 10.87 | 1.38 | 6.62 18 | 2.33 | 11.2 | 1.42 | 6.81 18½ | 2.4 | 11.51 | 1.46 | 7.0 19 | 2.46 | 11.82 | 1.5 | 7.19 19½ | 2.53 | 12.13 | 1.54 | 7.38 20 | 2.59 | 12.44 | 1.58 | 7.56 ----------------+------------+-----------+------------+-------- Bulk-percentage to be read on the side of the tube. * * * * * 2. Phosphates.--Phosphates are derived largely from the food, only a small proportion resulting from metabolism. The normal daily output of phosphoric acid is about 2.5 to 3.5 gm. The urinary phosphates are of two kinds: _alkaline_, which make up two-thirds of the whole, and include the {61} phosphates of sodium and potassium; and _earthy_, which constitute one-third, and include the phosphates of calcium and magnesium. Earthy phosphates are frequently thrown out of solution in neutral and alkaline urines, and as "amorphous phosphates" form a very common sediment. This sediment seldom indicates an excessive excretion of phosphates. _Quantitative estimation_ does not furnish much of definite clinical value. The centrifugal method is the most convenient. * * * * * TABLE FOR THE ESTIMATION OF PHOSPHATES AFTER CENTRIFUGATION _Showing bulk-percentages of uranyl phosphate (H[UO_{2}]PO_{4}) and the corresponding gravimetric percentages and grains per ounce of phosphoric acid (P_{2}O_{5}).--(Purdy.)_