In La Belle's reconstruction, that distance was determined to be 9½ inches. There is enough flexibility in the reconstruction that I suspect a distance of 10 inches was laid off by the designer, resulting in a rake to the outer face of the stem of 5 ft 4 inches.
The radii for the outer curve of the stem and the rabbet are both equal to the diagonal distance from point C at the bottom of the keel to point F (Figure 25) (Traitté…galères ca.1691:5–6). La Belle's designer would locate the center point G for the outer curve of the stem at the intersection of two small arcs drawn with points F and C as their centers. This way of finding the center of an arc given two endpoints and a radius is well documented in shipbuilding treatises (Dassié 1695:73–74; Duhamel 1758:166–167). Similarly, the intersection of arcs swung from points E and A at point H would be used as the center point for the outside curve of the rabbet (Figure 25). Since they do not share a common center but have the same radius, the stem arc and the rabbet arc are not concentric. This lack of concentricity resulting from such a drawing procedure is noted by Duhamel du Monceau in 1758 and is evident in the archaeologically preserved curves (Duhamel 1758:167). The theoretical curves reconstructed by these drawing steps superimpose exactly on those of the preserved part of the stem (Figure 26).
French author Ollivier writing in the 1730s states that "the length from the rabbet of the stem to the rabbet of the sternpost is measured from the rabbet of the stem at the point of the greatest projection of this timber to the rabbet of the sternpost at the level of the wing transom…" (Ollivier 1736:362). The wing transom (Figure 10) is located at the point of the maximum beam in the stern (MnM 1680:PH 178712–178715). The devis lists the height of the maximum beam in the stern as 9 ft 4 inches. Since part of the rabbet is preserved on the sternpost remains it can be projected upwards to point J at a vertical height of 9 ft 4 inches (Figure 21). Unlike for the stem, the heights for La Belle's sternpost reconstruction are measured from the top and not the bottom of the keel. In fact, other than for the stem height, the top of the keel is the baseline for all of La Belle's design dimensions. Such a switch in baselines is well supported by parallels in shipbuilding treatises and surviving drafts (Dassié 1695:73; Duhamel 1758:165,168; MnM 1686:PH 11393, 11409–11410).
The horizontal distance IB', from a vertical line dropped from point J to the back of the reconstructed outer sternpost, is 1 ft 6 inches (Figure 21). Although this measurement corresponds to the one listed in the devis, it is to the back of the outer sternpost and not the sternpost itself. However, it must be kept in mind that point B' is also the after endpoint of the top of the keel timber. The distance to the sternpost measured this way—IB—is 2 ft, and to the rabbet—IK—is 3 ft (Figure 21). NEXT
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