5

       We have now over two hundred analyses of the urine of students and others,
all of whom had a free choice of food; it will be our first duty to attempt to lay
down, as accurately as possible from the number of observations at our disposal,
standards for at least the more important constituents and to compare them with
the standards generally accepted for Europeans in a colder climate. For this
purpose it will be sufficient to strike an average for the total number of analyses
without taking any note of the particular caste of the subject from whom the urine
was obtained.

       1.Quantity of urine excreted in the twenty-four hours.—As our investiga-
tions extended over a period covering both the hot and cold weather in Calcutta,
the modification in the quantity of urine passed due to loss of fluids from the
lungs and in sweat may be, to a large extent, neglected in the average amount
obtained from the series.

       It will be evident from the above figures that the quantity passed varies
within very wide limits. In the average for each separate individual these limits
were between 650 c.c. and 2216 c.c. and when we examine the daily quantities
even wider limits are found—the lowest amount passed on one day being 330 c.c.,
and the largest quantity 2790 c.c. Variations more or less similar to these are
observed in all countries and depending, as they do, on a large variety of circum-
stances are not of much importance—wide variations in the quantity of urine
passed being quite compatible with health.

       The average quantity found over the whole series of two hundred observations
is 1177 c.c. This approximates very closely to that recorded for American
students ⁽¹⁾ in the winter, viz,, 1166 c.c., but, as would be expected, is below
the average amount voided by an adult male European, viz., 1200—1500 c. c.
per day.

       We may therefore fix our average for the quantity of urine passed in the
24 hours by Bengalis at from 1000—1300 c.c.

     2. The Specific Gravity.—In Europeans the average specific gravity of
normal urine is 1020 with variations in health of from 1015—1025, and, unless
under exceptional circumstances such as after the imbibition of large quantities
of fluids, it rarely falls below this; in certain cases where fluids are withheld for
some time the specific gravity may rise to 1035 or more.

       When we compare these standards with the results shown in the above table
it will at once be seen that there is a very marked difference. The limits of
variation found in the urine of the Bengali are very much wider than is the case
for the European; as a rule, the specific gravity is on a lower scale.

       On examining the average specific gravity—table I—of the urine of the
individual cases we find it ranges between 1006 in domes and 1024 in the case

⁽¹⁾ Manual of Physiology—Stewart.