The Rule for Casting the Tonnage

line, plan, timber, set, upper, breadth, counter, stern, middle and inches

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Then observe, aathe stern in its breadth rounds two ways, that is, both up and aft, the stern timber at the side will alter from that at the middle line, and must be thus drawn : take the round top of the upper counter, which is 10 inches, and set it below its knuckle at the middle timber in the sheer plan, and draw an horizontal line ; then take the round aft, which is 16 inches, (on a level,) and set it forward from the knuckle of the middle timber, and square it down to the line last drawn, and where it intersects will be the knuckle of the upper counter at the side. In the same manner set down 8 inches for the round-up, and forward 15 inches for the round aft, and that will be the knuc kle of the lower counter at the side ; then a curve being drawn, similar tothat at the middle timber, from one knuckle to the other, will form the upper counter at the side : then, to finish the lower counter at the side, set down 5 inches the round up, below the upper side of the wing transom in the sheer plan, and draw an horizontal line ; then take 7 inches, the round aft of the wing transom, and set it forward from the aft-side of the wing transom upon its upper side, and square it down to the line last drawn, and the intersection will be the aft-side of the side stern timber ; then a curve drawn similar to that at the mid dle from the side lower counter knuckle to the aft-side last set off, will represent the lower counter at the side. But as the straight line for the upper part of the side timber will not be parallel to that at the middle, owing to the stern narrowing upwards, its rake must be determined as follows ; upon any straight line set off 26 feet 8 inches, the breadth of the stern at the upper counter, and at the middle set off 16 inches, the round aft, then let an arch pass through this point and the half breadths of the stern on the line: this may be performed by a small drawing bow, or a mould swept with a radius equal to that segment. Now set off 12 feet, the half breadth of the stern at the top-timber line on each side the middle, to intersect the round aft at the upper counter, and through these intersections draw a line parallel to the other, and the distance from the line last drawn to arch in the middle is the distance that the side stern timber is from the after timbers, at the height of the top timber line ; then a line, drawn through this spot to the knuckle of the upper counter at the side com pletes the side counter timber.

Now the fore and aft view of the side counter timber may be drawn in the bo by plan, representing the half breadth of the stern. Draw an horizontal line across the after body plan, at the height of the upper side of the wing transom at the middle, thereon set off the half breadth of the wing transom from the half breadth plan, and there square down a line, and on that line set down 5 inches, or, what is the same thing, transfer the height of the wing transom at the side from the sheer plan ; then sweep an arch to cut the up per side of the wing transom at the side and middle, the centre of the radius being found in the middle line of the body plan ; then draw a horizontal line, as before, at the height of each knuckle transferred from the side timber in the sheer to the body plan ; then transfer the heights of the knuckles of the middle stern timber from the sheer up the middle line of the body plan ; then,to obtain the half breadth at each knuckle, the horizontal lines should be run from their heights in the body, to the half breadth plan, and their knuckles, squared down thereon from the sheer plan, and at those places their half breadth transferred to the body plan.—

Thus we should find the half breadth at the lower counter knuckle 14feet 6 inch. es, and at the upper counter knuckle 13 feet 5 inches; then set off these half breadths on their corresponding horizon tals from the middle line in the body plan, and by sweeping arches as at the wing transom from the heights at the side and middle line, the round-up of each counter would be represented ; then draw an hO. rizontal line in the body plan, at the height where the top-timber line cuts the side stern timber in the sheer plan, and on it set off the half breadth of the top. timber line, which is 12 feet, as taken from the half breadth plan. Draw ano ther horizontal line in the body plan, at the height of the top side, and on it set off 11 feet, its half breadth ; then draw a straight line from the knuckle at the up per counter and the two half breadths above it, and the upper part of the timber will be formed, and from thence to the lower counter the same line may be con tinued, only having it to curve between the knuckles ; then, to complete this timber between the knuckle at the lower counter and wing transom, three or more horizontal lines should be equally spaced and drawn across the body plan ; then se veral half breadths taken and set off the half breadth plan, and curves drawn through them; then,when these horizontal lines intersect the side stern timber in the sheer plan, they must be squared down to their corresponding lines drawn in the half breadth plan, and their several half breadths there taken and set off on their corresponding lines in the body plan ; then a curve, passing through those spots from the knuckle of the lowercounter to the wing transom at the side, completes the side timber in the body plan Now to complete the half breadth plan and the main half breadth and top-timber line abaft, thus square down to the half breadth plan where the height of breadth, the top-timber line, cuts the side stern timber in the sheer plan, and from thence transfer its height to the stern timber in the body plan, and there take its half breadth, and set off from the middle line of the half breadth plan upon the line last squared, down which is its ending at the outside ; from thence sweep a curve to the round aft of the stern at those places, and it is complete.

Now there only remains to complete the sheer plan, and the construction of the sheer draught or principal design will be completed ; and first set up the heights and lengths of all the decks thus: above the upper side of the gun deck already drawn, set up 7 feet 1 inch, all forward aft, and draw a curve parallel thereto, which will represent the under side of the upper deck, and another curve, drawn 3 inches above, and parallel thereto, will represent the upper side of the upper deck ; then above the upper side of the upper deck set up 6 feet 7 inches at tim ber F, and forward to the beak head ; then draw a curve through these heights, parallel to the upper decks, and that will be the under side of the forecastle; then draw. another curve 3 inches parallel above it, and that will be the upper side. Again, set up at timber 6, above the up per side of the upper deck, 6 feet 7 inch. es, and at the middle stern timber 6 feet 9 inches, and above those heights 3 inch es, drawing curves as before, the quarter deck will be represented. Set up, at timber 24, above the upper side of the quarter deck, 6 feet 5 incites, and at the midship stern timber 6 feet 7 inches, and above those heights 21, inches, and the round house deck will be represented as well as the before mentioned, at the mid dle line.

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