The device to which we
allude is shown at Figs. 104, 105 and 106. Fig. 104 shows only the index
hand, which is made of steel about 1/20" thick and shaped as shown. The
jaws _B''_ are intended to grasp the pallet staff by the notches _e_,
and hold by friction. The prongs _l l_ are only to guard the staff so it
will readily enter the notch _e_. The circle _d_ is only to enable us to
better hold the hand _B_ flat.
[Illustration: Fig. 104]
HOW TO MEASURE ESCAPEMENT ANGLES.
From the center of the notches _e_ to the tip of the index hand _B'_ the
length is 2". This distance is also the radius of the index arc _C_.
This index arc is divided into thirty degrees, with three or four
supplementary degrees on each side, as shown. For measuring pallet
action we only require ten degrees, and for roller action thirty
degrees. The arc _C_, Fig. 105, can be made of brass and is about 11/2"
long by 1/4" wide; said arc is mounted on a brass wire about 1/8"
diameter, as shown at _k_, Fig.
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