which divide the quarter of a circle into equal parts, and proceeding to the boundaries of the surface.

Fig. 3, a temporary frame or mould, framed to fit the curve ascertained by the various lengths of the lines, as described in Fig. 2; a b, a brace, to connect and support the extremities of the mould; c, a notch in the bottom of the mould, to give room for a thicker plank in the usual place of the keelson; dd, a noteh for the shear strake to lie in, to be flush with the outside of the mould.

Fig. 4, an iron clamp, a sufficient number of which are to be screwed to the moulds, and to the inside layer of plank, to keep the planks in contact with the moulds, until the next layer is put on and secured to the first.

Fig. 5, a piece of curved timber, which I term a breast trimmer, to give the shape of the upper part of the bow, and to receive the ends of the fore and aft planks, in a groove made for that purpose.

Fig. 6, perspective view of the moulds, set up on the core of the keel, with the breast trimmer, quarter timbers, and planks for keelson; A, the core of the keel and dead wood; B, the sole of the keel; a a, the quarter timbers; bb, the shear strake; cc, the breast trimmer.

Fig. 7, the first course of fore and aft planking; a, the breast trimmer; bb, the core of the keel; cc, dotted lines representing keys, put into mortices, to hold the timbers of the core together; dd, tenons, for the stern post to be fixed upon.

Fig. 8, shews the state of the vessel with the keel lowered, to admit the laying on of the first course of cross planking, from gunwale to gunwale.

Fig. 9, the last course of fore and aft planking; a, the stern-post driven on the tenons; bb, the cross planking of the keel; e, the scarf for the cutwater; d, a semi-circular

cular piece, to cover the ends of the planks, to render the appearance more uniform.

Fig. 10, a deck view; a a, stringers or deck clamps, (which are usual), connecting the sides and deck together; bb, the breast trimmer; c c, cross planks fore and aft of the fore scuttle, main hatchway, and after gangway; dd, cross planks to support the masts; e e, temporary joists to give the curve of the deck.

Fig. 11, the deck, cross planked, and prepared to receive the finishing layer of longitudinal planking; a ù, a dotted line, shewing the form of a stern of much greater strength than the usual square stern.

Fig. 12, a perspective view of the vessel, with the fore and aft deck planking, bulwarks, &c.

Fig. 13, a a, a line, shewing the curve of the deck when no weight is on it; bb, a dotted line, shewing the manner in which the deck is depressed, by placing a great weight on the middle, while, at the same time, the parts equidistant from the centre and each side, are raised by the pressure; which proves that every part of the deck contributes its share to support a weight placed in one spot.

I now proceed to describe the method I pursue in building a vessel of fifty or sixty tons upon my new system, and in this description, I must, of necessity, include some points that are not new, of which I do not claim the invention; but as I have previously shewn, in a distinct manner, what are my improvements in constructing ships, boats, and other vessels, they need not again be distinguished from those parts of the old system, which I use in combination with my improvements.

Method of Building.—I first take a piece of soft wood for my model, which I form to the given proportions of length of keel, breadth of beam, and depth of hold, from

a scale

a scale of not less than a quarter to half an inch to a foot; I prefer the latter for accuracy. To shew the water lines on the model, it may be glued up of pieces one inch thick, more or less, as may be thought proper; the joints will be always perceptible, and may be rendered more so by a pencil. After rubbing it with linseed oil, it may, previously to being cut, be placed in water, to shew how the vessel will sit. The utmost care should be taken in the form of the model, as it will be a perfect miniature of the vessel when built.

The keel of the model is let into a groove, to be removed at pleasure.

I divide the model, fore and aft, into as many equal parts, aa, Fig. 1, as I intend to make moulds, with two cuts, horizontally bb, or diagonally cc, to form the harping moulds; and I place the model in a box, the exact width of the model, with a groove in the bottom of the box to receive the keel, and keep it firm; the box having a perpendicular cut at right angles to guide a saw, with which I cut the model in equal spaces, and perfectly true. From each of these sections I obtain the curve of my moulds, as shewn in Fig. 2, by describing the quarter of a circle cc, dividing it into parts, and drawing the lines from the centre, through the divisions, to the outside.

I then draw a quarter of a circle on a floor, or other broad surface, and divide it into the same number of equal parts, and draw lines from the centre, through the divisions, to a distance rather more than half the breadth of the intended vessel, and, taking the length of the lines from the model, I slightly drive a nail in each line on the floor, at the corresponding distances of those, on the model, according to the scale adopted, and bend a thin lath round the nails; this gives the curve of half the

mould,