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Anonymous

"Watch and Clock Escapements A Complete Study in Theory and Practice of the Lever, Cylinder and Chronometer Escapements, Together with a Brief Account of the Origin and Evolution of the Escapement in Horology"



Fig. 142 is a side view of Fig. 141 seen in the direction of the arrow
_y_. We have mentioned a chariot to which the detent is attached, but we
shall make no attempt to show it in the accompanying drawings, as it
really has no relation to the problem in hand; i.e., explaining the
action of the chronometer escapement, as the chariot relates entirely to
the convenience of setting and adjusting the relation of the second
parts. The size, or better, say, the inside diameter of the pipe at _C_,
Fig. 143, which holds the locking jewel, should be about one-third of a
tooth space, and the jewel made to fit perfectly. Usually, jewelmakers
have a tendency to make this jewel too frail, cutting away the jewel
back of the releasing angle (_n_, Fig. 143) too much.

A GOOD FORM OF LOCKING STONE.
A very practical form for a locking stone is shown in transverse section
at Fig. 143. In construction it is a piece of ruby, or, better, sapphire
cut to coincide to its axis of crystallization, into first a solid
cylinder nicely fitting the pipe _C_ and finished with an
after-grinding, cutting away four-tenths of the cylinder, as shown at
_I_, Fig.


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