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117

the state of dryness in which the ingredients existed orig-
inally in the enamel ; for we have seen, that by drying the
phosphate of lime in a heat of 212°, (after which it had the
appearance of being as dry as possible,) it yet contained so
much moisture as to yield a gain of 8 grains in the analysis.
On the other hand, when ignited, its state is driven to the
opposite extreme, and there is a loss of 16 grains. It is im-
possible, however, that the materials could exist in the teeth,
in a state of dryness to be compared with that produced by
exposing them to such a high temperature. And it appears
but reasonable to conclude, that the real quantity of mois-
ture lies nearer to that given by the heat of 212°, than to that
given by ignition, and consequently that the 16 grains
lost
by exposure to such a high temperature were chiefly water.
Phosphate of lime ....
Bone or roots of teeth, yielded by analysis, in 100 grains,
... 58
Carbonate of lime, 4
Gelatine, 28

90
Water of composition and loss - 10

100
The teeth of adults yielded on analysis, in 100 grains,
Phosphate of lime, ... 64
Carbonate of lime, g
Gelatine, 20

90
Water of composition and loss, 10

100
Specific gravity of adults teeth, - 2.2727