thus showing that the striking part of a clock is older than the
clock itself. It seems strange to us to say that many of the earlier
clocks were strikers, only, and had no dials or hands, just as if
you turned the face of your clock to the wall and depended on the
striking for the time. Keeping this action of the verge escapement
in mind we can easily understand its application, as made by De
Vick, in Fig. 26, where I have marked the same pallets A B. A tooth
is just escaping from pallet B and then one on the other side of
the wheel will fall on pallet A. Foliot, verge and pallets form one
solid piece which is suspended by a cord, so as to enable it to
swing with little friction. For the purpose of making the motions
very plain I have left out the dial and framework from the drawing.
The wheel marked "twelve hours," and the pinion which drives it, are
both outside the frame, just under the dial, and are drawn in dash
and dot. The axle of this twelve-hour wheel goes through the dial
and carries the hand, which marks hours only. The winding pinion and
wheel, in dotted lines, are inside the frame. Now follow the "great
wheel"--"intermediate"--"escape wheel" and the two pinions, all in
solid lines, and you have the "train" which is the principal part
of all clocks. This clock has an escapement, wheels, pinions, dial,
hand, weight, and winding square. We have only added the pendulum,
a better escapement, the minute and second hands in over 500 years!
The "anchor" escapement, Fig. 27, came about 1680 and is attributed
to Dr. Hooke, an Englishman. It gets its name from the resemblance of
the pallets to the flukes of an anchor. This anchor is connected to
the pendulum and as it swings right and left, the teeth of the escape
wheel are liberated, one tooth for each two swings from rest to rest,
the little push on the pallets A B, as the teeth escape, keeping the
pendulum going. It is astonishing how many, even among the educated,
think that the pendulum drives the clock! The pendulum must always be
driven by some power.
[Illustration: Fig. 25--Verge Escapement]
[Illustration: Fig. 26--De Vick's Clock of 1364]
[Illustration: Fig. 27--Anchor Escapement]
[Illustration: Fig. 28--American Anchor Escapement]
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