In the present instance the
addendum line _w_ becomes the controlling arc, and it will be further
noticed on the large drawing that the line _B h_ at its intersection
with the arc _n'_ approaches nearer to the arc _w_ than does the line
_B f'_ to the pitch circle _a_; consequently, the inner angle of the pallet
should not in this instance be carried down on the arc _n'_ so far to
correct the error as in the ratchet tooth.
Reason tells us that if we measure ten degrees down on the arc _n'_ from
its intersection with the addendum circle _w_ we must define the
position of the inner angle of the entrance pallet. We name the point so
established the point _r_. The outer angle of this pallet is located at
the intersection of the radial line _A b_ with the line _B i_; said
intersection we name the point _v_. Draw a line from the point _v_ to
the point _r_, and we define the impulse face of the entrance pallet;
and the angular motion obtained from it as relates to the pallet staff
embraces six degrees.
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