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140 HUNTER ON THE TEETH.
OF THE MANNER OF SHEDDING OF TEETH.
An opinion has commonly prevailed, that the first set of
Teeth are pushed out by the second ; this, however, is very far
from being the case : and were it so, it would be attended with
a very obvious inconvenience ; for, were a Tooth pushed out by
one underneath, that Tooth must rise in proportion to the
growth of the succeeding one, and stand in the same proportion
above the rest. But this circumstance never happens : neither
can it ; for, the succeeding Teeth are formed in new and dis-
tinct sockets, and generally the Incisorcs and the Guspidati of
the second set are situated on the inside of the corresponding
teeth of the first set
; and we find, that in proportion to the
growth of the succeeding Teeth, the fangs of the first set decay,
till the whole of the fang is so far destroyed, that nothing
remains but the neck, or that part of the fang to which the
Gum adheres, and then the least force pushes the Tooth out.
It would be very natural to suppose, that this was owing to a
constant pressure from the rising Teeth against the fangs or
sockets of the first set : but it is not so for, the new Alveoli
;
rise with the new Teeth, and the old Alveoli decay in proportion
as the fangs of the old Teeth decay, and when the first set falls
out, the succeeding Teeth are so far from having destroyed, by
their pressure, the parts against which they might be supposed
to push, that they are still inclosed, and covered by a complete
bony socket. From this we see, that the change is not pro-
duced by a mechanical pressure, but is a particular process in
the animal ceconomy.
I have seen two or three Jaws where the second temporary
Grinders were shedding in the common way, without any Tooth
underneath; and in one Jaw, where both the Grinders were
shedding, I met with the same circumstance.
A remarkable instance of this sort occurred to me in a lady
who desired me to look at a loose Tooth, which I found was the
last temporary Tooth not yet shed. I desired that it might be
drawn out, and told her it was of no use, and could not by any