The piece H can be permanently attached to the rod F.  We show separate at Figs. 113 and 114 the slide G N on an enlarged scale from Fig. 109.  Fig. 114 is a view of Fig. 113 seen in the direction of the arrow e.  All joints and movable parts should work free, in order that the center I may be readily and accurately set.  The parts H F are shown separate and enlarged at Figs. 115 and 116.  The piece H can be made of thick sheet brass securely attached to F in such a way as to bring the V-shaped groove at right angles to the axis of the rod F.  It is well to make the rod F about 1/8” in diameter, while the sliding center I need not be more than 1/16” in diameter.  The cone point n should be hardened to a spring temper and turned to a true cone in an accurately running wire chuck.

[Illustration:  Fig. 115]

[Illustration:  Fig. 116]

The hollow cone end m of I should also be hardened, but this is best done after the hollow cone is turned in.  The hardening of both ends should only be at the tips.  The sliding center I can be held in the V-shaped groove by two light friction springs, as indicated at the dotted lines s s, Fig. 115, or a flat plate of No. 24 or 25 sheet brass of the size of H can be employed, as shown at Figs. 116 and 117, where o represents the plate of No. 24 brass, p p the small screws attaching the plate o to H, and k a clamping screw to fasten I in position.  It will be found that the two light springs s s, Fig. 115 will be the most satisfactory.  The wire legs, shown at L, will aid in making the device set steady.  The pillar E is provided with the same slides and other parts as described and illustrated as attached to D.  The position of the pillars D and E are indicated at Fig. 110.

[Illustration:  Fig. 117]

[Illustration:  Fig. 118]

We will next tell how to flatten F to keep H exactly vertical.  To aid in explanation, we will show (enlarged) at Fig. 118 the bar F shown in Fig. 109.  In flattening such pieces to prevent turning, we should cut away about two-fifths, as shown at Fig. 119, which is an end view of Fig. 118 seen in the direction of the arrow c.  In such flattening we should not only cut away two-fifths at one end, but we must preserve this proportion from end to end.  To aid in this operation we make a fixed gage of sheet metal, shaped as shown at I, Fig. 120.

[Illustration:  Fig. 119]

ESCAPEMENT MATCHING DEVICE DESCRIBED.

[Illustration:  Fig. 120]