Page 23 - My FlipBook

TARTAR. 1 9

of the rapidity of its formation, being in an inverse

ratio to this.
All the varieties of tartar are composed principally
—
of the same elements, phosphate of lime, fibrin, fat,
and animal matter being contained in them all, though
in various proportions. The fact that some varieties
are soluble in acids, and others not, has been adduced
to prove that they are entirely different in their com-
position. This, however, is accounted for on another
hypothesis : in the softer varieties, the phosphate of
lime is so protected by the fat and the animal matter
that, under ordinary circumstances, acid can not come
in contact with it; but the dense varieties are very

soluble, because the acid readily comes in contact with
the calcareous material.
Its origin.—It is a precipitate of the saliva,—or at
least the phosphate of lime, and probably the fibrin,
comes into the mouth with the saliva ; while perhaps
the fat and other animal matter are deposited from
the mucus. In all cases in which this substance is

formed upon the teeth, the saliva has a definite alka-
line character, holding in solution the phosphate of
lime, which, by the action of the acid mucus upon the
saliva, is precipitated.
Persons of a lymphatic temperament, or a tendency
toward it, with muscles of a soft, flabby texture, hair
light, teeth of a rather inferior quality, and a free flow