r turning through
90 deg.. With four pins in the escape wheel and a suitably proportioned verge
the escape wheel advances in steps of 45 deg. and beats eighths of a second.
The growing trend in this period to standardize the timing of sporting
events in intervals of fifths of a second is reflected in still another
model having five pins in the escape wheel and beating tenths of a
second. By the nature of the verge in this escapement, it will be seen
that the number of beats must be twice the number of pins in the escape
wheel, leaving no way to secure an odd number of beats per second, hence
the 1/10-second model. This must have been a less desirable form because
of the much smaller verge required, plus the problem of accelerating so
much mass from a dead stop 600 times per minute.

[Illustration: Figure 17.--A TIMER DIAL that is probably either
experimental or very early. Note that the fractions of a second
(quarters) are shown on the outside dial instead of on a separate dial.
This dial was converted at the factory for use as the base of a
hairspring vibrating stand. A dial different from this but having the
same arrangement of circles is known. (In author's collection.)]

Figure 16 illustrates a dial for this 1/10-second model which the author
found in a lot of unused parts left over when the factory closed. The
watch had an 18-size 3/4-plate movement with grained nickel finish. The
escapement is special, as we have seen, but the fork, roller, and balance
action are conventional. There are five jewels, four to support the
balance staff and an impulse jewel. The barrel arbor comes through the
top plate with a square, as in a keywind watch, but is fitted with a
winding handle, so that a key is unnecessary. This handle appears to be
an afterthought, because on the earlier models (those with serial numbers
below 1,000), the barrel arbor is short, barely long enough to attach the
winding handle; later this arbor was made longer. Patent 204274 issued to
Benjamin Wormelle of Brighton, Massachusetts, on May 28, 1878, the same
date as Wales' escapement patent, may have suggested this winding handle.
On watches with higher serial numbers, there are two arrows on the handle
to show the direction to wind.

The earliest of these timers had a slide on the side of the case to stop
the movement by means of a piece of thin spring steel applied roughly
tangentially to the smooth rim of the three-arm, solid steel balance
wheel. When