Note 17 — THE URINE.

The specific gravity of the urine materially depends upon those causes which act diuretically, and upon the quantity of fluids swallowed, which, if taken in excess, of course increases the watery portion of the urine, and vice versa. The density of the urine is ascertained by an instrument called an “Hydrometer,” which, upon being immersed in the urine, indicates its specific gravity. The usual specific gravity of healthy human urine varies from 1.010 to 1.015, while the temperature ranges from 75 degrees of Fahrenheit to 120. The quantity averages from two to three pints per diem, but depends not only upon the quantity of fluids consumed, but also upon the nature of the food, vegetables generating more urine than animal substances. In infancy and old age, the temperature of the urine is below this standard, but nearly equivalent to each other; whereas it is only at the period of puberty that the temperature noted exists.