l of alcohol,
and also leaves the work stained. We can accomplish this operation
quicker, and save alcohol, by putting the cylinder with the wax on it in
a very small homeopathic bottle and corking it tight. The bottle is then
boiled in water, and in a few seconds the shellac is dissolved away. The
balance to most cylinder watches is of red brass, and in some instances
of low karat gold; in either case the balance should be repolished. To
do this dip in a strong solution of cyanide of potassium dissolved in
water; one-fourth ounce of cyanide in half pint of water is about the
proper strength. Dip and rinse, then polish with a chamois buff and
rouge.

[Illustration: Fig. 181]

In staking on the balance, care should be observed to set the banking
pin in the rim so it will come right; this is usually secured by setting
said pin so it stands opposite to the opening in the half shell. The
seat of the balance on the collet _D_ should be undercut so that there
is only an edge to rivet down on the balance. This will be better
understood by inspecting Fig. 181, where we show a vertical section of
the collet _D_ and cylinder _A_. At _g g_ is shown the undercut edge of
the balance seat, which is folded over as the balance is rivetted fast.

About all that remains now to be done is to true up the balance and
bring it to poise. The practice frequently adopted to poise a plain
balance is to file it with a half-round file on the inside, in order not
to show any detraction when looking at the outer edge of the rim. A
better and quicker plan is to place the balance in a split chuck, and
with a diamond or round-pointed tool scoop out a little piece of metal
as the balance revolves. In doing this, the spindle of the lathe is
turned by the hand grasping the pulley between the finger and thumb. The
so-called diamond and round-pointed tools are shown at _o o'_, Fig. 182.
The idea of this plan of reducing the weight of a balance is, one of the
tools _o_ is rested on the T-rest and pressed forward until a chip is
started and allowed to enter until sufficient metal is engaged, then, by
swinging down on the handle of the tool, the chip is taken out.

[Illustration: Fig. 182]

[Illustration: Fig. 183]

In placing a balance in a step chuck, the banking pin is caused to enter
one of the three slots in the chuck, so as not to be bent down on to the
rim of the balance. It is seldom the depth between the cylinder and
escape wheel will need be c