e, Second foot-hook, from 6 to 10 feet long, and from 6 to 13 inches deep, thickness 1⁄6th less than depth. This curve, when of great size, is valuable as, breast-hooks—curved timbers stretching horizontally within and at right angles to the bow-timbers, to support the bow.
f, f, f, Knees, the one wing nearly at right angles to the other; from 2 to 9 feet in length of wing; depth at middle as much as possible; thickness from 4 to 12 inches,—generally required about 3 1⁄2 feet in length of wing, and from 6 to 8 inches thick. Knees, when large, suit for high rising floors.
Fig. h is a valuable piece, and easily procured by bending the young plant; when cut, it forms two second foot-hooks.
Figs. a, b, c, d, e, are suitable, though the part cut off by the dotted line be awanting. In good work, this plan is often followed, and a cross-chock put on. (Vid. s, left side of the cross-section of a vessel thus timbered, page [20]). By this {19} mode of building, vessels can be constructed from much straighter timber, and the vessels are superior, from being more elastic; but from the nicety and expense of the work and waste of timber, the practice is not much in use.
{20}
Cross-section of a Vessel at midships—knees not inserted.
A first foot-hook alternates with each floor, and second foot-hook, alongside, extending from o to q; and a top-timber, or third foot-hook, alternates alongside of each second foot-hook, and chock extending from q to a. These timbers are bolted together, and constitute a frame or double rib; and the skeleton is composed of a series of double ribs (several inches separate, of course wider above than lower down, as the timbers decrease in thickness), to within a little of the bow and stern, where the timbers are usually placed singly, without framing. {21} In large vessels a fourth futtock is used; thence straighter timber is suitable.
The knees occupy the position at x, stretching horizontally along the inside of the vessel and end of the beams.