"The section No. 1 also shows the timbers are of various dimensions, as it is not absolutely necessary they should be all of one size, only they should be tapered in proportion, so as to keep the proper angle; but they should be all of the same dimensions the other way, so as to produce an even surface for the planking, as at present; and I should always keep my timbers to their fullest dimensions from outside to inside, as the more I increase the surface of my abutments, the greater the stability of the vessel, - always bearing in mind that I am constructing an arch, to be self-abutted in every direction. I can reduce the thickness of the planking, and increase the thickness of the timbers, and, by so doing, greatly increase the strength of the vessel; and as strength and stability are the principal objects I propose to obtain by my improvements, in those parts of the vessel at or near the head or stem, where the ribs form a sharper or more acute angle at the keel, as shown by Figs. 7 and 8, I would keep the line of the timbers more to the circle, to admit of the timbers which cross the keel being cut out of trees of moderate dimensions, without the grain running too much across, and to fill out the shape with what is technically termed dead wood or chocks, as shown by Figs. 7 and 8, which should be secured to the rib, and bolted to its fellow piece; which, by increasing the surface of the abutments, adds stability to the arch, and proportionate strength to the vessel.
"If any objection should be made about the quantity of dead wood or chocks accumulating, by adhering strictly to the rule laid down as relative to Figs. 7 and 8, I would wish it to be understood, that if the ribs were prepared for those parts as they are at present, only to diminish them from the top to the bottom, as before stated, and bolt them firmly together, and to the keel, as at present, the vessel would be infinitely stronger than by the ordinary mode, but would not, in my opinion, be of equal strength and durability as if executed agreeably to the rule laid down in Figs. 7 and 8; as, on my plan, if the whole of the keel, stern-post, and the dead wood, were all carried away, the frame of the vessel would remain firm and secure, and would only have lost the trifling portion of strength she had acquired from her keel and dead wood being affixed to her frame. It may be proper here to remark, that on my improved mode of ship-building, every additional piece of timber affixed to it from the first rib or frame to the last plank, all and every additional piece so affixed brings with it its proportionate addition of strength and stability to the vessel, beyond its own weight.
Even what is technically termed dead wood, on my principle, brings its proportionate addition of strength and stability to the vessel, if it is put on, and secured to each rib, and bolted to its fellow as directed.
"The beams on which the decks lay should be secured to the sides of the vessel in the usual manner; but as room is considered a great object between decks, and the present decks, beams, and planking take up from 10 and 11 to 14, 16, and 18 inches, according to the size of the vessel, and the number of decks, etc, I propose cutting oak scantling to the size or thickness of the decks,- say about 6 or 8 inches square, according to the width of the vessel, - keeping the curve of the deck as much as possible, - say about 7 or 8 inches in the width, of about 28 or 30 feet, and the scantling about 6 or 8 inches, taking about the same quantity of timber as at present used in beams and planking. These I bolt firmly together (see Fig. 5,) after the same manner as the ribs of the hulls, with about three-quarter or seven-eight bolts, according to the rate or tonnage of the vessel. The scantling should be all the length across the vessel, and being bolted together as above, would be found of great strength; but to increase the strength as might be required, I would truss two together at about 6 or 8 feet apart, as in middle-deck Fig. 5; or a truss, constructed as Fig. 14, might be inserted into each scantling; or a rule joint self-abutted chain, as Fig. 13, might be let into the edge of the scantling, for the same purpose: and they should continue through the sides of the vessel, having a stout nut-screw and plate, to enable them to secure the sides firmly to the deck, - thus answering a double purpose; and by having fewer or more of them, the decks may be made of any additional strength required, with an even surface underneath, yet will not take up half the space occupied by the present decks.
I merely name these methods, if additional strength should be required; but it is my opinion there will be sufficient strength without them. In vessels where expenses or first cost were not an object, the timbers might be prepared with a circular groove in the centre, (see Fig. 10,) in which groove a strongly twisted rope of oakum might he put, which, being left rather large, would, when screwed up tight, form a strong and tough tongue or key, and also a stop for the caulking. The decks, if required, could be done in the same way, and they might be caulked on both sides, if requisite, and if any objection should arise about the joints of the decks running across the ship, they might board it the other way with thin boards (as see Fig. 5), or the scantlings might run from head to stern, kept to the curve, and bolted together the same as the others; in which case it would form an arch, the abutments of which were seemed, but would not be so strong as the other way. Fly. 4 shows how the timbers come to a finish at the head, and circular stern of the vessel.
The keel or stern-post is not shown, as it is only to show how the timbers finish, and also what very short pieces may be occasionally used; as the strength of the arch does not so much depend on the length of the pieces, as on the increased surface and effectual security of the abutments. It will be understood that spaces for port holes in ships of war can be left without materially diminishing the strength of the vessel.