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66 MECHANICAL DENTISTRY AND METALLURGY.

of No. 60 tin-foil, a little wider than the outside surface
of the gum, and by commencing at one side with the broad
end of the ivory-pointed carver, No. 3, burnish the tin
down smoothly and uniformly over the entire surface,
occasionally using the pointed end to work between the
teeth, and the straight blade of carver No. i to cut the
tin from around the teeth. The inside of the model is
treated in the same way, except that a narrow, V-shaped
piece is cut from the tin before placing it on the palatal
Fig. zT-

surface, to avoid folding, and that the entire outer edge of
the plate is trimmed around. The stippling is done with
an ordinary blunt-pointed excavator, or with a suitable
engine plugger that will give a reacting blow. If done
delicately and closely, the effect of the stippling is very
pleasing."
Manner of Flasking.—The flasking or investing of the
case should receive quite as much care as in rubber work.
First mount the model high in the shallow half of the flask,
especially designed for celluloid. Now pour in thin plaster
until it just reaches the lower edge of the plate. When
the plaster is set sufficiently, trim it to the proper shape for
separating, and then coat it with the liquid soap. Place
the deep ring of the flask in position and very carefully fill