y part yields, force in a wedge-shaped
plugger and fill the opening in above-described manner; condense,
burnish, and trim alternately until the surface is level with the
cavity-margin. By extending the folds from the orifice to the base of
the cavity, the liability of the tin to crumble or come out is
effectually prevented, and by putting it in with a wedge-shaped plugger
it is pressed out into all depressions of the walls.

A later method of filling with tape or rope is to use wedge-shaped
pluggers with sharp serrations, filling the _ends_ of the cavity, and as
the two parts approach each other that next to the wall should be in
advance of the rest, thus an opening will be left in the center which
can be filled with a smaller tape or rope.

Another old method: Take a piece of foil and roll it into a hard ball;
then gradually work it into the cavity, being careful to have
sufficient around the margin.

Still another suggested method: Roll a piece of foil into a loose ball,
place it in the cavity, and pass a wedge-shaped plugger into its center.
This has the effect of spreading the tin toward the walls of the cavity,
the opening to be filled with folds in a way already described. The
wedge is used as often as it can be made to enter, filling each opening
with folds; then condense the surface, trim, and burnish.

[Illustration: FIG. 10.]

The English give the Americans the credit of first using cylinders.
Anyhow, Dr. Clark, of New Orleans, in 1855, used them made from
non-cohesive gold, and also from gold and tin in alternate layers. (See
Fig. 10.)

Cylinders were used which were a little longer than the depth of the
cavity, introduced with wedge-shaped pluggers around the walls, each one
being closely adapted to the margin; then another row was added, which
was forced firmly against the preceding, continuing this process until
the cavity was full. The wedge, having a smooth end and sides, is forced
into the center so as to drive the tin toward the sides of the cavity,
being careful not to split the tooth; the opening is then filled with a
cylinder. Now force a smaller-sized wedge into the center of the last
cylinder, and into the opening introduce another cylinder, proceeding in
this manner until the filling is solid. Then condense the ends of the
cylinders, trim, and burnish. For the same operation more recent
pluggers are wedge-shaped, with sharp, deep serrations. In these cases
the filling is retained by the g