SHIP-BUILDING. 



14 feet 1 1 inches ; at 16, 14 feet 5 inches ; at 18, 14 feet ; at 

 20, 13 feet 3I inches ; at 22, 1 2 feet 5 inches ; at 24, 1 1 feet 

 7 inclies ; at 26, 10 feet 5 inche'? ; at 28, 9 feet I inch ; at 30, 

 6 feet 7 inches ; at 32, 5 feet 10 inches ; at 34, 4 feet ; and 

 at 36, 2 feet. 



Now to end this diagonal, it mult be drawn in the body-plan 

 thus ; fet up the middle line from the bafe 12 feet 2 inches, 

 and on the Safe, from each fide of the middle line, 1 1 feet 

 9 inches, then draw the diagonal ticked line, as (hewn in 

 Piatt I. In draughts, diagonal Imes are diltinguilhed by 

 red ink. Then in the body-plan draw the half-fiding of the 

 ftem in the fore-body, and the half-fiding of the ftern-poft in 

 the after-body : for the latter fet up 26 feet above the bafe, 

 and at that height fet off from the middle line 10 inches in 

 the half-fiding of the pott at the head, and 9 inches in the fore- 

 body, the half-fiding of the ftem at that height ; and on 

 the bafe line 75 inches from each fide the middle line, the 

 half-fiding of poft and Item at the heel ; then draw ftraight 

 lines to each fpot fet off, and the half-fiding of the Itern-poil 

 and ftem will be reprefented in the body-plan. Now to 

 complete or end the diagonal line on the half-breadth plan, 

 its height or interfeAion at the poil and ftem muft be taken 

 in the body-plan, and transferred relpettively to the fore- 

 fide of the rabbet of the ftem, and aft -fide of the rabbet of 

 the poft in the ftieer-plan, and from thence let them be 

 fquared down to the middle line of the half-breadth plan ; 

 then take with compaffes the half thicknefs of the poll and 

 ftem in the body-plan, in the direftion of the faid diagonal 

 line, and fet them off refpettivcly from the middle line in 

 the half-breadth plan, on the lines latt fquared down ; and 

 from the inlerfedlion as a centre, fweep an arc towards the 

 midftiips, with compaffes opened to the thicknefs of the 

 rabbet taken diagonally ; then a fair curve drawn through 

 all the fpotii as above fet off, touching the back of the arcs, 

 will form the diagonal line at the floor-heads, as fhewn in the 

 half-breadth plan, Plate I. 



Now may the timbers, as far as the floor-fweeps are ufe- 

 ful, be completed in the body-plan below the lower height 

 of breadth, beginning at dead-flat : thus, take the half- 

 breadth of the floor diagonal at in the half-breadth plan, 

 and fet it down the diagonal from the middle line in the 

 body-plan ; then take the half-breadth of the floor-fweeps 

 in like manner, and fet it off' from the middle line in the 

 body-plan on the horizontal fine before drawn at its height, 

 and from the interfeftion extend the compaffes to the half- 

 breadth of the floor diagonal, and fweep an arc upwards 

 from the dead-rifing, which is fix inches at ® ; then with the 

 reconciling-fweep, which is of a long radius compared with 

 the others, unite the lower-breadth fweep and floor-fweep 

 together ; for the more the midftiip-frames deviate from the 

 fegmentof a circle, the lefs will be the rolhng motion of the 

 fhip ; unite the floor-fweep with the upper edge of the rabbet 

 of the keel with a curve or ftraight fine, and the midfhip- 

 timber will be formed below the lower breadth. In the fame 

 manner may be formed the frame-timbers B, D, F, H, and 

 K, in the fore-body, and 2, 4, 6, 8, 10, to 24 in the after- 

 body, by fetting off the half-breadth of each frame's diagonal 

 as at 0, their correfponding heights of breadths, main half- 

 breadths, and centres of each fweep, as before direfted, and 

 by reconciling the lower-breadth fweeps and floor-fweeps 

 together, and ending them into the rabbet at the keel ; thus 

 the midfhip part of the body will be formed from K for- 

 ward to 24 abaft. 



Hence it may be readily conceived, that bodies full or 

 ftarp, either for burthen or velocity, may be conftrufted by 

 altering the radii of the different fweeps ; and unlefs bodies 

 of fljips could be conftruded from feme geometrical 



figure, a more certain method than the above cannot be 

 given. 



The body being thus far formed, that is from K forward 

 to 24 abaft, proceed to prove it by horizontal lines, and 

 finifh the remaining part forward and aft. Thefe lines 

 are generally called water-lines, as the fhip's bottom at the 

 furface of the water, fuppofing the keel kept parallel there- 

 to, would be of the fame figure as thofe lines reprefented in 

 the half-breadth plan, with the addition of the thicknefs of 

 the bottom plank in that direftion. The upper one is called 

 the load-water-line, or line of floatation, when the veflel is 

 fuppofed fit for fea, which will be treated of more particularly 

 hereafter ; the other water-lines may be equally divided be- 

 tween the upper or load-water-line, andupperedgeof the keel 

 or rabbet. Although a fhip may draw more water abaft than 

 forward for her beft failing trim, yet to keep the feveral 

 water-lines horizontal, or parallel with the upper edge of the 

 keel, is the moft ufeful m conftruftion; and the water-lines, 

 as reprefented in the half-breadth plan, form curves, limiting 

 the various half-breadths of the fhip at the heights of their 

 correfponding lines in the body-plan. They are generally 

 drawn with green ink, but in Plate I. with correfponding 

 dotted lines, and are reprefented by ftraight lines in the 

 fheer-plan ; and if parallel with the keel they will be hori- 

 zontal lines in the body-plan, but if the veUel is to be con- 

 ftruCted to draw much more water aft than forward, the 

 water-lines will not of courfe be parallel with the upper 

 edge of the keel; then, owing to their various heights at each 

 timber in the fheer-plan, they will form curves at thofe 

 heights in the body-plan, and the more they vary from an 

 horizontal fine, the lefs accurate will the hmits of their half- u 

 breadths be delcribed in the half-breadth plan. 



In Plate I. the upper horizontal water-line is 20 feet 

 above the lower edge of the keel; and between that and the 

 upper edge of the rabbet of the keel, are equally divided 

 four more wafer-lines, as in the fheer-plan. The water-lines 

 may now be drawn in the half-breadth plan from the body- 

 plan, as far as the timbers are there formed ; thus, continue 

 the water-lines aft from the Ihcer-plan acrofs the body- 

 plan, then take off with compaffes, or a flip of paper and 

 pencil, their various half-breadths from the middle line, to the 

 places where the feveral timbers interfecl each water-line, and 

 fet them off on t heir correfponding timbers from the middle line 

 in the half-breadth plan ; then to end each water-line fqnare 

 down where they interfeft the fore-part of the rabbet at the 

 ftem, and aft-part of the rabbet at the itern-poft in the 

 fheer-plan to the middle line of the half-breadth plan ; then 

 take the half-fiding of the ftem and the itern-poft at each 

 water-line from the middle line in the body-plan, and fet 

 them refpeftively on the lines laft fquared down from the 

 middle line in the half-breadth plan; from thence, as the 

 centre, with compaffes opened to the thicknefs of the bottom 

 plank, make a fweep, the back of which is the ending of the 

 line. Then complete the fore and after ends of each water- 

 line with curves, as in the half-breadth plan, avoiding all in- 

 flefted curves or hollow water-lines at the fore part, as they 

 may be drawn by arcs of circles, although their centres may 

 be without the limits of the plates of fhip-building. 



Now the whole of the body may be completed under the 

 lower height of breadth, obferving to fweep each timber 

 below its height of breadth, as before direfted ; then by 

 taking off the half-breadth of each timber, where they in- 

 terfeft the water-lines from the middle line in the half- 

 breadth plan, and fetting them off on their correfponding 

 water-lines from the middle line in the body-plan, curves 

 palling through thofe fpots will fhape the timber ; but to 

 end them into the rabbet, or complete the heeling, the keel 



muft 



