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Chapter XXII
The Construction of the Crossbow (Continued)
The Steel Bow, The Bow Irons and the Stirrup
Dimensions of the Bow (Fig. 58, Next Page)
Length - Between extremes, 2 ft. 6 in.
Width - At centre of length, 1 5/8 in., with a gradual reduction to
a width of 1 in. at 2 in. from each end.
Thickness - At centre of length, 1/2 in., with a gradual reduction to
3/8 in. at 2 in. from each end. Width across enlarged parts of ends, each
1 1/2 in.
The bow is flat on all sides, with squared edges.
For the ends of the bow, into the notches of which the loops of the
bowstring fit, see fig. 69, p. 114.
The normal bend of the bow, taken from the centre of its length, inside
its curve, to the centre of a thread connecting its ends, is 4 1/2 in.,
C - D, A, fig. 58, next page.
B, Fig. 58, next page, shows how the arms of the bow are slightly canted
up from its centre. If a thread is held from the centre of one end of the
bow to the centre of its other end, as per dotted line, it should be 1
in. higher at its centre than the upper edge of the bow, as the latter
lies on its side on a table, x- x, B, fig. 58.
If the bow had not this upward cant, its bowstring would press so hard
on the top of the stock that it would be unable to propel the bolt with
proper force. The friction of the bowstring against the stock would prevent
the string from acting freely when the bow recoiled from a bent position.
All the best steel bows were made in this manner, especially those used
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