Precisely the same conditions obtain at the point _u_, which
holds the same relations to the exit pallet as the point _o_ does to the
entrance pallet _C_.
ANGULAR MOTION OF ESCAPE WHEEL DETERMINED.
The arc (three and a half degrees) of the circle _a_ embraced between
the radial lines _A b_ and _A e_ determines the angular motion of the
escape wheel utilized by the escape-wheel tooth. To establish and define
the extent of angular motion of the escape wheel utilized by the pallet,
we lay off seven degrees on the arc _a_ from the point _o_ and establish
the point _n_, and through the point _n_, from _B_ as a center, we sweep
the short arc _n'_. Now somewhere on this arc _n'_ will be located the
inner angle of the entrance pallet. With a carefully-made drawing,
having the escape wheel 10" in diameter, it will be seen that the arc
_a_ separates considerably from the line, _B f'_ where it crosses the
arc _n'_.
It will be remembered that when drawing the ratchet-tooth lever
escapement a measurement of eight and a half degrees was made on the arc
_n'_ down from its intersection with the pitch circle, and thus the
inner angle of the pallet was located.
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