Page:Timber and Timber Trees, Native and Foreign.djvu/71

CHAP. IX.]

—No. 7 broke short: 8 and 12 with 7 to 13 inches length of fracture; 9, 10, and 11 with 15 inches scarph-like splintery fracture.

The Tables V. and VI. each refer to parcels of six pieces, which were taken from trees of good average quality and size, moderately seasoned, and fit to be applied to architectural works, the specific gravity varying from 670 to 905 in one set, and 780 to 1005 in the other. Of the twelve pieces tested, the elasticity of two, after the weight of 390 lbs. was removed, was perfect. One piece recovered its straightness to within .312 inch, while of the remainder, nine in number, the elasticity was in all something better, though not quite perfect.

The deflections varied under this weight of 390 lbs. from 3.125 to 3.625 inches in one set, and from 1.5 to 1.75 inch in the other, the ultimate deflections at the crisis of breaking varying from 5.25 to 11.00 inches, and 4.125 to 9.50 inches, respectively; while the