(3) Acetone Test:—To 5 c.c. of urine in a test tube add a crystal of sodium nitro prusside. Acidify with glacial acetic acid, shake a moment, and then make alkaline with ammonium hydrate. A purple color indicates acetone.
(4) Diacetic Acid Test:—To 5 c.c. of urine in a test tube add an excess of a 10% solution of Ferric chloride. A Burgundy red color indicates diacetic acid.
Quantitative Test for Ammonia.
To 25 c.c. of urine add 5 c.c. of a saturated solution of potassium oxalate and 2 to 3 drops of phenolphthalein.
Run in from a burette decinormal sodic hydrate, to a faint pink color. Then add 5 c.c. of formalin (40% commercial) and again titrate to the same color.
Each c.c. of the decinormal alkali used in this last titration equals 1 c.c. of n/10 ammonia, or .0017 gm. of ammonia. Multiply this by the number of c.c. n/10 sodic hydrate used in the last titration; this gives the number of grams of ammonia in 25 c.c. urine.
Note:—The potassium oxalate and the formalin must both be neutral to phenolphthalein.
1 kilogram = 2.2 pounds.
1 calorie = The amount of heat necessary to raise the temperature of 1 kilogram of water 1 degree Centigrade.
1 gram fat = 9.3 calories.
1 gram protein = 4.1 calories.
1 gram carbohydrate = 4.1 calories.
DIETS.
In the diet tables following, the vegetables listed, excepting lettuce, cucumbers, celery, and raw tomatoes, are boiled. In the very low carbohydrate diets they are thrice boiled. When possible to obtain the figures, the analyses for boiled vegetables have been used. It has been estimated that four-tenths of the carbohydrate will go into solution when such vegetables as carrots and cabbage are cut into small pieces, and thoroughly boiled, with changes of water. It must be remembered that bacon loses about half its fat content when moderately cooked.