Directions for a practical course in chemical physiology / W. Cramer.

  • Cramer, William, 1878-1945.
Date:
1920
Catalogue details

Licence: In copyright

Credit: Directions for a practical course in chemical physiology / W. Cramer. Source: Wellcome Collection.

    86/150 (page 76)
    DEPOSIT OP OTHER CALCIUM SALTS IN URINE. Urinary Deposits of Calcium Salts. From acid urines :— Calcium oxalate, either in the form of highly refractive octahedra, “envelope” shape, or in the form of ovoid bodies, “ dumb-bell ” shape. They are insoluble in acetic acid; soluble in hydrochloric acid. A considerable sediment-of calcium oxalate is pathological. From alkaline urine :—- Calcium carbonate.—Spherical or ovoid crystals with concentric striation. Readily soluble in acetic acid with effervescence. Common deposit in the urine of herbivorous animals. AMMONIA. Experiment 137.—Make urine alkaline with sodium carbonate solution, and warm. Note the smell of ammonia. A moist piece of red litmus paper held over the mouth of the tube turns blue. Within what limits does the average amount of ammonia excreted by a normal person in twenty-four hours vary % How can it be increased ] How can it be diminished ? PREPARATION OF UREA FROM URINE. Experiment 138.—Place about 100 c.c. of urine in a porcelain capsule and evaporate in a water-bath to about 20 c.c., so that the urine is now concentrated to a syrup. Cool by floating the capsule on cold water. Filter into a beaker, and place beaker in cold water. Slowly add while stirring an equal volume of cold 50 per cent, nitric acid (pure). (Why can fuming yellow nitric acid not be used ?)