Page 111 - Nicolaes Witsen & Shipbuilding in the Dutch Golden Age

Figure 2.103. Data for the rising of the wales (p. 70). Witsen’s original table has been digitally altered to show the Dutch text in English. Scanned image modified by Emiel Hoving.
flutes we sometimes see three w ales at the height of the scuppers as well as on large ships of the first half of the seventeenth century, like the Prins Willem and Wasa.
The wales were intended to streng then the ship longi- tudinally. This explains why shipbuilders had not cut these important constructional elements for the re ar gunports before the mid-seventeenth century. Not cutting the wales was related to the fl attening of the dec ks, which still fol- lowed the sheer in the e arly decades of the century, thus keeping all gunports between wales. Guns, of course, were better operated on a horizontal platform, which was also more comfortable. The decks were l aid more and more level; yet the wales still followed the rise of the sheer. As a consequence, they crossed the gunports aft and had to be cut. This can first be observed on an engraving by Roel- ant Saverij of the Aemilia, Admiral Maarten Harpertsszoon Tromp’s flagship in 16 32, although a dmittedly there are three versions of the engraving, one of which shows the gunports neatly placed between the w ales. When exactly the change came about remains uncertain.
The rise of the wales depended on the judgment of the shipwright and had direct consequences for the height of the vessel. Toward the end of the century the trend was to make the wales ever flatter, until in the eighteenth century
the question of interrupting the wales no longer arose, as they ran parallel to the fl at decks. However, this design did influence the construction. A flush ship has a greater tendency to hog th an an arched ship, so it is to be ex - pected that we fi nd the introduction of diagonal framing systems in the eighteenth c entury to prevent this prob- lem. With the strongly rising seventeenth-century ships this problem occurred less often.
The rise of the wales also depended on the purpose of the ship: men- of-war were fl atter than merchant vessels. The shipwright could also expre ss his personal prefer- ences. Witsen supplies us with a couple of rather strange tables for calculating the rise of the wales (see figs. 2.102 and 2.103), varying from “ 7⁄100” (7 percent? ) to “5⁄100” and for ships varying from 40 feet to 180 feet in length. What he meant exactly with his main categories—7, 61⁄2, 6, 51⁄2, and 5(feet)—is unclear, but thesetables dounderscore the fact that the rise of the wales was open to choice.
Bending the w ale planks, which were often 15 to 20 centimeters thick, by scorching must have demanded much insight and experienc e. Thus, it is not surprising that one of the most sharply curved wales on the Wasa shows a crack at the point of its greatest deflection. This bending process could go wrong even then.
How Ships Are Built in Holland Today
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