[Illustration: Fig. 66]

Now such other condition might very easily exist, that bringing the
jewel pin forward to the position indicated by the dotted lines at _D_,
Fig. 66, would remedy the defect described and illustrated at Fig. 64
without any other change being necessary. We do not assert, understand,
that a hole too large for the jewel pin is either necessary or
desirable--what we wish to convey to the reader is the necessary
knowledge so that he can profit by such a state if necessary. A hole
which just fits the jewel pin so the merest film of cement will hold it
in place is the way it should be; but we think it will be some time
before such rollers are made, inasmuch as economy appears to be a chief
consideration.


ABOUT JEWEL-PIN SETTERS.

To make a jewel-pin setter which will set a jewel pin straight is easy
enough, but to devise any such instrument which will set a jewel so as
to perfectly accord with the fork action is probably not practicable.
What the workman needs is to know from examination when the jewel pin is
in the proper position to perform its functions correctly, and he can
only arrive at this knowledge by careful study and thought on the
matter. If we make up our minds on examining a watch that a jewel pin is
"set too wide," that is, so it carries the fork over too far and
increases the lock to an undue degree, take out the balance, remove the
hairspring, warm the roller with a small alcohol lamp, and then with the
tweezers move the jewel pin in toward the staff.