On the starboard side of the vessel in this drawing, the futtock templates were cut down along the adjusted upper rising curve. This was done to show how the top timber templates could then be slipped in with their surmarks aligning with the adjusted upper surmarks on the futtock templates.
Such a reduction in slope of the diagonal runs in the upper hull is clearly visible in a stern view of the fifteenth-century votive model from Mataro in Catalonia, Spain (Figure 46a) (Winter 1956). Figure 54 is a photograph of a research model I built while studying the use of Mediterranean moulding in fifteenth-century Venetian ship construction. It depicts how a ribband run "normal" in the upper hull (at the bocha) significantly flattens the slope of the longitudinal curve defined by the lower narrowing and rising adjustments (Figure 54). In the construction of galleys, for which the exact height of the oarsmen is vital, the quantification of such additional adjustments would have been critical and appears in the historical records by the late fifteenth century (Bellabarba 1993:284–286; Lane 1934:29–31). Similarly, as the layout and functionality of gundecks gained in importance over the course of the sixteenth and seventeenth centuries, quantitative control over the upper design curves in sailing vessels became equally critical.
The shape of the midship section impacts on the relative amounts of narrowing and rising required to have fine curves low in the hull and yet retain fullness in the upper hull. The rising of a midship section with a narrow floor actually results in a significantly greater narrowing of the curves along horizontal lines in the lower hull than in the upper hull. In our example the need for substantial narrowing of the floor results in excessive narrowing at deck level. The additional offset scale applied at the breadth in Figure 49p controls the splaying out of the upper futtocks and reduces the amount of narrowing in the upper hull. In Figure 49p the port futtock templates were rotated at the bilge as they were simultaneously tilted out. In Mediterranean moulding the surmark on the bilge served as either the anchor point for pivoting or a reference point for rotating the futtock in order to separately control the narrowing of the hull at the top of the futtock mould. Thus the scales that appear at the bilge on the futtock templates in Figure 49q were not derived directly. They were marked off as the futtocks were tilted and rotated (Figure 49p). It is the offsets on a separate splaying-out [upper narrowing] staff that directly quantify the adjustment to the narrowing of the hull. Note that in Figures 49p and 49q a new set of upper rising offsets was used to reset the rising of the breadth curve.
As the final step, the frame outlines generated by adjusting the positions of the templates are joined to the keel. For simplicity, in these examples straight lines were drawn tangent to the bilge curves (Figure 49o–q), although treatise evidence indicates that reverse curves were commonly drawn by flipping one of the two templates and using it as a pattern. NEXT
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