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       This is the more remarkable when the almost entirely vegetable nature of
the diet is considered. Bunge ⁽¹⁾has called attention to the fact that among men
and animals the craving for salt is limited, for the most part at least, to those
living on vegetable food. On a purely animal diet there is no desire for salt.
Bunge explains this phenomenon in the following manner. Most vegetable foods
contain a large quantity of potassium and these salts on absorption react in the
blood with sodium chloride, giving rise to potassium chloride and potassium
sulphate; both these salts are removed at once by the kidneys since they are
both practically foreign to the blood; so that the blood in this way loses some of
its sodium chloride; hence the craving for more salt with vegetable food.

       We were therefore prepared to find a high average in the salt excretion of
the Bengali as he had a free choice in the quantity of salt taken with his vege-
table food. But such is not the case; the quantity got rid of by the kidneys is
actually lower than in Europeans.

       These results are in striking contrast to those shown in Table XIII, where the
intake and output of salt is very excessive. This, however, is a subject to
which we shall return when dealing with the metabolism of the Bengali.

        The quotient Δ/Na Cl% (Δ=freezing-point of urine) representing the ratio of
the total concentration to the sodium chloride concentration varies relatively
in Europeans, within narrow limits—diet, according to Von Koranyi, having no
fluence.

       As has already been shown,⁽²⁾the limits of variation met with in the
Bengali are very much wider, being in the above series from .72 to 1.80, com-
pared with variations in Europeans lying between 1.23 and 1.69. The quotient
Δ/Na C1% in the Bengali nearly approaches unity.

           The second table—Table II—gives the results of observations on some of
the other constituents of the urine not mentioned in Table I. These include
uric acid, phosphates, sulphates, and in a few cases the organic sulphates.
Although the number of these analyses may be considered too limited they serve
to give some indication of what the standards under these headings of the
urine of Bengalis work out to be.

            As already stated, investigations having for their object the further study of
the different forms of nitrogenous waste products other than urea are at present
being carried out. These will include in addition to urea—

          (a) The ammonia nitrogen—that is, the nitrogen found in the form of
               ammonia salts which liberate free ammonia on the addition of a
               fixed alkali.

                              ⁽¹⁾ Bunge.—Physiologie des Menschen, Vol. II, 1901.

                              ⁽²⁾ McCay.—The Lancet, June 1907.

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