Nicolaes Witsen and Shipbuilding in the Dutch Golden Age

Table 1: Comparison of Witsen’s and Van Yk’s shipbuilding formulas.

250 Tables A key dimension in Witsen’s formulas is the width (thickness) of the inboard face of the stem, whic h was calculated as one inch for every ten feet of the ship’s total length. Almost half of Witsen’s formulas (about 46 percent) are based on the width of the inside stem. Van Yk’s formulas also use this reference point but to a much lesser degree (about 10 percent). Compared with Witsen, Van Yk uses a wider range of criteria to obtain the dimensions of components, with reference points like the keel, wing transom, and the main dimensions of the ship. While many of the formulas in both Witsen’s and Van Yk’s treatises remained constant throughout the seventeenth century, some changed in response to the fashion of the day. With this second group of formulas (indicated with italics in the table below), we should therefore pay considerable attention to the period in whic h they were applied. Key L = Length of ship between outsides of stem and stern W = Width (beam) of ship, measured over frames (without planking) D = Depth in hold, me asured between top of keel and top of lower deck beams without camber i.s. = width of inside stem = 1 ⁄10 inch per 1 foot L (or 1 cm per 112 cm L) Witsen’s Formulas Van Yk’s Formulas Ship’s dimensions: L : W : D = 20 : 5 : 2 Main dimensions of ships: W = 1 ⁄4 L D = 3 ⁄4 W − (height of bulwark + height “’tween decks”) Or: D = 40%–50% W Keel: Width = 11 ⁄2 i.s. Height = 11 ⁄4 i.s. Keel: Length = 9 ⁄10 L Width = 1 inch per 7 feet W Height = a little bit less than its width Length of joints = 5 inches per 1 inch width of keel (two bolts per 2 feet length of joint) Stem: Width outside = 3 ⁄5 to 3 ⁄4 i.s. Breadth = in the middle, 3 × i.s. Height = D + deck rising + “’tween decks” + forecastle deck Or: 2 ⁄11 L Or: 11 ⁄60 L Rake = 28 ⁄29 height of stem Stem: Height = D + deck rising (1 inch per 10 feet) + height “’tween decks” + anything above that Width = 1 ⁄10 inch per 1 foot L Width outside stem = width i.s. − 1 or 2 inches Breadth = in the middle, 2 × width; above and below, a bit more Rake = not specified Table 1. Comparison of Witsen’s and Van Yk’s shipbuilding formulas. 251 Pinas Drawings Witsen’s Formulas Van Yk’s Formulas Sternpost: Length (height) = W + deck rising + “’tween decks” (or height of upper deck) Or: = height i.s. Width = stem Breadth top = 11 ⁄5 i.s. Breadth foot = 5 × i.s. Top square = wing transom Rake = 1 foot per 6 feet length (height) Sternpost: Length = trim (1 ⁄50 foot per 1 foot L) + D + deck rising (2 inches per 10 feet) + height “’tween decks” + height of wing transom Width = i.s. Breadth top = 11 ⁄4 i.s. Breadth middle: 11 ⁄3 breadth top Breadth foot = 1 ⁄4 foot per 1 foot length Raking = 1 ⁄7 foot (fluyts 1 ⁄14 foot) per 1 foot length Wing transom: Length = 2 ⁄3 W Or: = width of bottom Width, height, and camber = 1 ⁄11 length (for every foot, 1 inch) [doubtful] Or: = i.s. Wing transom: Length = 3 ⁄4 W Height = height of keel Width = 4 ⁄5 height Camber = 1 inch per 2 feet length Fashion pieces: Thickness = 5 ⁄6 width of wing transom Or: 1 ⁄2 i.s. Width = 2 × width of wing transom Fashion pieces: Thickness = 2 ⁄3 wing transom Width = a minimum of 2 × thickness Transoms: 2 ⁄3 wing transom Or: 4 ⁄5 i.s. Transoms: Thickness = 3 ⁄4 wing transom Stern timbers: Length above transom = length of stern timber Thickness = 2 ⁄3 i.s. Tumble home: 3 ⁄5 transom Stern timbers: Length above transom: = height of sternpost Thickness = 1 ⁄2 i.s. Width = a bit more than the thickness Tumble home = 2 inches inward per 1 foot of length Bottom: Width = 2 ⁄3 W Bottom: Width = length of wing transom (3 ⁄4 W) 252 Appendix Witsen’s Formulas Van Yk’s Formulas Planking: Thickness = 1 ⁄4 i.s. Planking: Thickness = according to table: Length of shipThickness of planks 40–60 feet 2 inches 60–80 feet 2[1 ⁄2] inches* 80–100 feet 3 inches 100–120 feet 31 ⁄2 inches 120–140 feet 4 inches 140...