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with the new formed basis of the tooth ; whatever eminences
or cavities the one has, the other has the same, but reversed,
so that they are moulded exactly to each other.
" In the incisores it lies in contact not with the sharper
cutting edge of the pulp, or tooth, but against the hollowed
inside of the tooth ; and in the molares it is placed directly
against their base, like a tooth of the opposite jaw. It is
thinner than the other pulp, and decreases in proportion as
the teeth advance. It does not seem to be very vascular.
The best time for examining it is in a foetus of seven or eight
months old.
" The enamel appears to be secreted from the pulp above
described, and perhaps from the capsula which encloses the
body of the tooth. That it is from the pulp and capsula,
seems evident in the horse, ass, ox, sheep, &c. therefore we
have little reason to doubt of it in the human species."
Now whether we are to understand, by the words " the
pulp above described," that which he speaks of as connected
to the membrane of the first pulp, or the first pulp itself, he
has left us quite at a loss to determine. At all events with
the nature, use, and formation of this second pulp he seems
to be utterly unacquainted ; for he first leaves us, as be-
forcsaid, in doubt, whether its use be to form the cortes
striatus of the first teeth, a thing next to impossible ; and
again he says, that in proportion as the teeth advance, it be-
comes thinner, which is actually the very reverse of what
really happens. I need hardly add, that there are no such
pulps as he describes to be found on the bases ofthe temporary
grinders, (another inaccurracy which he has strangely fallen
into,) but merely a thickening of their proper membranes.
As the sacs of the permanent teeth advance, the sockets
of the temporary ones become enlarged, and little niches are
formed in the internal plate of the alveolar processes answering