Page 53 - Nicolaes Witsen & Shipbuilding in the Dutch Golden Age

two 1 How Ships Are Built in Holland Today
The seventeenth-century Dutch shipbuilding method was a proportional sys- tem in which shipbuilders applied traditional formulas inherited from their pre- decessors. The treatises of Witsen (1671) and Van Yk (1697) provide two sets of such formulas, and their ac curacy can generally be c onfirmed from the m any ship specifications that are still in existence today.
The formulas determined the ship’s main dime nsions as well as the sizes of almost every structural component. Although termino logy in the f ormulas may have differed from ship yard to ship yard, the out comes, if compared with each other, were always practically identical. Thus, there was a direct connection be- tween the main dimensions of the ship and those of its parts.
We can distinguish two kinds of formulas. In the first category are those for- mulas that reflect fixed principles of proportion and g overn the s izes of each major part relative to the whole; these formulas were subject to very few adapta- tionsuntiltheendof thewoodenshipbuildingera.Ontheotherhand,wefind formulas for par ts that c hanged over the years due to f ashion trends (lik e the width between the counter timbers or the length of the beakhead), ship function (a man-of-war versus a merc hantman or a fi shing vessel), a new “theoretic al approach” (such as the introduction of three-deckers), or the c haracteristics of particular bodies of water (e.g., some fl uyts were espec ially designed for the shallow waters around Taiwan and of the Ganges in India). The formula for the length of the beakhead is a good example of one that changed over time. Early in the seventeenth century its size was one fifth of the ship’s length; by the end of the century it had shrunk to one eighth. A c omparison of Witsen’s and Van Yk’s shipbuilding formulas are presented in table 1 in the appendix.
Witsen distinguishes 122 step s in the bu ilding process, which we w ill fol- low one b y one in thi s chapter after we ac quaint ourselves with his remarks about ship dimen sions. There are also a number of phases in the method he describes; these phases—which required a c hoice in certain proportions or di- mensions that would affect the ship’s performance in ways that were evident to the shipbuilder—will also be highlighted.
Ship Dimensions
(262 II 4 6) Circumstance, and di ering practices, change the build and shape of ships: with w hich I do not mean to sa y that, though these pro- portions may be good, that other proportions should not be equall y good, although I know of no other, let alone better.
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