The difficulty lies in the fact that there is rarely direct evidence of the design method used. Most hull remains provide at least some direct evidence of determining the vessel's original shape, its structural characteristics, and even its assembly sequence. How the shipwright determined or designed the shape of the vessel most often has to be deduced from the above analyses in combination with comparative archaeological and documentary evidence.

Occasionally the archaeological ship reconstructor is fortunate enough to encounter the remains of a vessel on which shipwrights' design marks have been preserved. Such marks, most commonly referred to as surmarks, are simply straight lines carved into some of the framing timbers (Figures 2a, 3). There are various tool marks that result from the construction of a vessel, and all types of tool marks can contribute to our understanding of how a vessel was built. What makes surmarks exceptional is that they provide direct evidence of how a vessel's shape was conceptually defined. Surmarks indicate in three-dimensional space the coordinates of points that were used to define the curvature of the hull (Figure 1). In other words, these marks are evidence for systems of design with which shipwrights were able to generate measurements for the hull's curvature, and this allowed the shaping of timbers that would define the hull shape during construction.

La Belle is one of only seven vessels dating from the fourteenth to the eighteenth centuries on which inscribed design marks have been discovered and documented to date (see Part II). Despite the rarity of archaeological design marks, they are prevalent in European documents relating to ship design from the fifteenth to eighteenth centuries (Barker 1988:550; Bellabarba 1993; Rieth 1996; 2003a; Rieth and Pujol 1998:156–159; Sarsfield 1989)(Figure 4a, b). From these documents it is known that surmarks were integral to the design process. Thus in the case of La Belle, as with a handful of other "marked" vessel remains, the fact that these marks were incised into the timbers may account for their preservation, discovery, and uniqueness. Such marks are more likely to survive than drawn or painted marks, which may have been present on other wrecks but are no longer visible.

La Belle has the most extensive and complete set of such marks. It is most extensive not only in the absolute number of marks but also in the percentage of the hull shape these marks define. Furthermore, La Belle has two sets of surmarks along its bilges (Figure 3) while other "marked" vessels have only one. When superimposed in cross section, La Belle's design marks define oblique straight lines, i.e., diagonals (Figure 5a, b). These distinguishing features of the distribution, number, and placement of La Belle's surmarks associate it with a graphic design system of "geometric fairing with diagonals," which was in use in French shipbuilding in the late seventeenth and eighteenth centuries. NEXT