SHIP-BUILDING. 



trimmed by a mould made to the fiieer of the (hip, and the 

 fore and aft-arms by the flight of the cheeks laid off on the 

 floor, there will fometimes be a very difagreeable throat, 

 which cannot happen when trimmed by the above method. 

 Althou'Th the iidc-arm may not hang fo much as the (heer of 

 the fhip? yet it will not look difagreeable, becaufe the throat 

 of the cheek is the only part that takes the flight. 



To lay-off the Head-Rails. — Strike in the perpendiculars 

 Z and Y from the fore-fide of the figure, and foremoft end 

 of the uppei- rail in the (lieer-plan, fig. i, down to the half- 

 breadth -plan, fig. 2. Determine on the half-breadth of 'the 

 lacing, as at i, z,fig. 3, as the foremoft end of the upper rail 

 comes againft it. The after end fays againft the plank at 

 the beak-head timber, from whence Itrike a ftraight line to 

 the lacin<T at its fore end. Then fet off the fiding of the 

 rail, allowing the thicknefs of the lining, and ftrike the line 

 P, or outfide ; which being the fight-fide of the rail when in 

 its place, is the propereit to be laid off. 



Strike the horizontal line 32 at the upper part of the 

 foremoft end of the upper rail, in the flieer-plan, ^_f . 1. 

 Then fquare up to the line 32 the aft-fide of the ftem- 

 timber 20, and as many lines at equal diftances as may be 

 needful, and number them i, 2, 3, &c, above the line 32, 

 as (hewn in fig. i. Set off the fame ftations from perpendi- 

 cular Y, on the middle hne in the half-breadth plan, fig. 2, 

 and fquare them out to the line P, or outfide of the main- 

 rail, numbering them, as before, at the middle line ; then 

 fquare them out from the hne P. Take the diftances from 

 the line 32 in the fheer-plan, fig. l, to the upper and lower 

 parts of the main-rail at each perpendicular line, and fet them 

 off on their correfponding numbers in the half-breadth plan, 

 fig. 2, which was fquared out from the line P ; and then, by 

 pinning a batten to thefe fpots, it will give the form of the 

 main-rail, and it will (hew the fame form, when in its place, as 

 that in the (heer-plan, fig. i. Where the lines fquared out 

 from the middle line in the half-breadth plan interfeft 

 the infide of the main-rail, ftrike them from thence fquare 

 from the line P to the rail already laid off, and take the 

 diftances on thefe lines from the line P to the upper part of 

 the rail, and fet them down from the line 32 in the (heer- 

 plan,^^. I , on their correfponding perpendiculars ; which will 

 give the infide of the main-rail in the ftieer-plan, fig. 1 ; as 

 the ticked line, which rifes above the middle of the rail 

 forward, being the upper line, and below towards the 

 after end as the after part, falls below the outfide. The in- 

 fide of the rail at the lower edge muft be fet off in the fame 

 manner in the ftieer-plan, in order to lay off the timbers 

 exadly. 



Strike the ticked line in the plan of the rails in the half, 

 breadth plan, fig. 2, which is the line to which the chamfer 

 at the under fide of the rail the mouldings are inteaded to 

 be wrought to, This muft hkewife be hid off in the (heer- 

 plan, becaufe in a thwartfhip view this is the proper fight of 

 the lower edge of the rail ; for the lower part of the rail in 

 the fheer-plan (which was firft laid off in order to lay off 

 the rail to its proper cant in the half-breadth plan) may now 

 be rubbed out, when the rail is fuppofed to be chamfered 

 or wrought. 



Id the half-breadth plan, fig. 2, where the lines fquared 

 out from the middle line interfeft the ticked line before-men- 

 tioned, ft.rike them from thence fquare from the line P to the 

 lower part of the rail laid off ; then take the diftances on 

 thofe lines from the line P to the lower part of the rail, 

 3nd fet them off from the line 3 2 in the (heer-plan, fig. I . 

 on their correfponding perpendiculars. This gives the lower 

 •part of the rail in the (heer-^Un, at the chamfer, being the 

 r»ght part of the ml when trimmed and in iti place, 



Before the main-rail is canted, as in the half-breadth plan, 

 fig. 2, the proper form of it cannot be afcercained in the 

 fheer-plan, ^y. i ; for the rail, when canted in order to nuke 

 the mould, muft be gradually diminifhed from one end to the 

 other, and from thence transferred to the (heer-plan ; for 

 inftance, the middle line at the after-part of the rail in the 

 (heer-plan, is the aft-part of the rail at the outfide ; fo that 

 from thence to the fore-fide of the rail (hews lefs than the 

 rail in the middle ; alfo, at the foremoft end the rail will not 

 (hew fo much as it does in the half-breadth plan ; whereas 

 in the middle it (hews the fame. 



Before the middle rails can be canted in the half-breadth 

 plan, fig. 2, to their proper fpread, proceed in the follow- 

 ing manner ; ftrike an horizontal line from where the aft-fide 

 of the ftcm-timber 20, in the flieer-plan, _^. i, interfeft.; 

 the upper fide of the upper cheek, as the line 27, in fig. 3. 

 Take the heights from the upper fide of the upper cheek, at 

 the perpendicular line 7, in the (heer-plan,^. i, to the 

 upper and lower parts of the three rails L, M, and N, and fet 

 them up from the horizontal line before-mentioned in fig. 3, 

 as you fee ticked at L, M, and N. Then take the diftances 

 from the middle line in the half-breadth plan, ^.2, at the 

 hne 7, to the outfide of the main-rail ; likewife to the 

 infide, and the ticked line for the chamfer of the rail at the 

 under fide ; and fet them off on their correfponding lines ia 

 fig. 3, and draw the thwartlhip feftion of the main-raiL 

 Set off in the half-breadth plan the half-thicknefs of the knee 

 S Y of the head, and the moulding of the upper cheek C C,- 

 then take the half-thicknefs of the knee at 7, or aft-fide of 

 the ftem-timber in the half-breadth plan, fig. 2, and fet it 

 off from the middle hne u in the plan of the timber, fig. 3, 

 on the line 27. Then determine the breadth of the timber 

 at the upper fide of the cheek, and pin a batten to the 

 curve for the outfide of the timber. Then in the plan of 

 the timber ,^^. 3, determine on the half-breadths of the middle 

 rails L and M ; and transfer them from thence to the half- 

 breadth plan, fig. 2, at the aft-fide of the ftem-timber. 

 Then fet off the diftance of the foremoft end of the rails 

 from the middle line, and ftrike in the two lower or middle 

 rails N, O, in the half-breadth plan, fig. 2. 



The middle and lower rails being determined in the half- 

 breadth plan, fig. 2, the outfides of them, being the fight- 

 fides, are the propereft to be laid off. The outfide of the 

 middle rail is marked O, and the outfide of the lower rail 

 N. Where the upper fides of the middle rail M, and 

 lower rail L, in the fheer-plan, ^^. i, interfeft the aft-fidc 

 of the hair-bracket H, ftrike the horizontal lines 33 and 

 34, anfwerable to thofe in the half-breadth plan, fig. 2. 



Where the fines i, 2, 3, &c. which are fquare from the 

 middle line in the half-breadth plan, fig. z, interfeft the lines 

 O and N, let them be fquared out from the lines O and N, 

 in the fame manner as was performed for P. Then take the 

 diftances from the lines 33 and 34, in the fheer-plan, ^^. i, 

 (at the fame perpendiculars as before,) to the upper fide of 

 the middle and lower rails, and fet them off in the half- 

 breadth plan, fig. 2, from their correfponding lines O and 

 N, on the fines fquared out. This gives the form of the 

 upper fides of the middle and lower rails, which is fufhcient 

 to fhew the method of laying off each rail, agreeable to 

 their different cant or fpread. The lower fide of the rails 

 js formed by a diminifhing line to the moulding or depth of 

 the rail at each end. 



It is very feldom that the middle and lower rails are 

 laid oft on the floor only ; the main or upper rail, when 

 trimmed, is gotten up into its place, and moulds are there 

 made to the head-timbers, and then the middle and lower 

 rsils are fpread and equally divided thereon between the upper 



rail 



