About the best material for such guard points
is either aluminum or phosphor bronze, as such material is lighter than
gold and very rigid and strong. At Fig. 83 we show a side view of the
essential parts depicted in Fig. 82, as if seen in the direction of the
arrow _v_, but we have added the piece which holds the jewel pin _D_. A
careful study of the cut shown at Fig. 82 will soon give the horological
student an excellent idea of the double-roller action.
We will now take up and consider at length why Saunier draws his
entrance pallet with fifteen degrees draw and his exit pallet with only
twelve degrees draw. To make ourselves more conversant with Saunier's
method of delineating the lever escapement, we reproduce the essential
features of his drawing, Fig. 1, plate VIII, of his "Modern Horology,"
in which he makes the draw of the locking face of the entrance pallet
fifteen degrees and his exit pallet twelve degrees. In the cut shown at
Fig. 84 we use the same letters of reference as he employs.
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