adjoining these; then the double teeth of the first set are exchanged
for their smaller successors of the second. The eye-teeth after a time
begin to make their appearance; and then more double teeth; making in
all twenty-eight teeth, and occupying in their developement from the
seventh to the fourteenth year of age. They are not, however, yet
complete; for between the latter date and the twenty-first year four
more teeth appear, called the wisdom teeth, making the adult set or
permanent teeth to amount in all to thirty-two teeth. It should be
observed, that whilst this is the most usual course in which this set
appear, the line of succession is sometimes different.

THEIR VALUE AND IMPORTANCE.

It would seem almost unnecessary to say a word upon so self-evident a
truth, and yet perhaps the full extent of this statement is not
generally appreciated. It has not, perhaps, occurred to the minds of
all, that upon the right position and arrangement of the teeth the
beauty and expression of the countenance much depends. But so it is;
for however regular and perfect the general features, if the teeth are
irregular or deficient, an unpleasing expression, proportionate to the
extent of the displacement, is inevitably produced. Now every mother
should be alive to this fact, that she may early apply to the dentist
to have any error of the above nature rectified, before it is too late.

On their complete and entire state also depends the perfection of
utterance and articulation. The child, for instance, makes no attempt
at articulation until it has acquired several teeth; this faculty
becomes also exceedingly imperfect during the process of changing them;
from this time it continues to improve, until again it is permanently
impaired in old age, when they are finally lost. And so again, if a
child lose merely a single tooth from the front of its mouth, lisping
will result; or if a supernumerary or irregular tooth be present, the
articulation will be abrupt and imperfect:--the former plainly showing
the importance of the entireness of the series, and the latter, the
necessity of regularity in their arrangement and position.

The teeth, however, are chiefly important in relation to the part they
sustain in connection with digestion, viz. the mastication of the food.
By this act the food, after being received into the mouth, is mixed
with the saliva and broken down, till it becomes of an uniform pulpy
consistence, fit for