Extracting Diagnostic Information from Historic Ship Timber Surface Marks: The Case Of La Concorde/Queen Anne’s Revenge (1710-1718)

Abstract

The analysis of historical ship timbers has been a principal facet of maritime archaeological research since the earliest days of the discipline. Among their many qualities, the natural and anthropogenic impressions left on their wooden surfaces in particular hold a great informational potential that is not often exhaustively examined. The qualitative and quantitative discernment of such markings can provide new insights into the artifacts’ archaeological deposition as well as their historical use beyond what can be found in written records.

Until recently, previous archaeological research on this subject was limited and tended to incompletely record such features, thereby also limiting the amount of information which can be derived from them. This is firstly because their examination has been confined to isolated examples within a collection rather than a comprehensive comparison of all impressions in the wooden remains found across an entire archaeological site or shipwreck. Secondly, this is because they have primarily been studied using more commonly available methodologies such as standard photographs, illustrations, written notes, tracings, and rubbings. Not only are these techniques potentially damaging to the source material, but they are also often imprecise, limited to a two-dimensional perspective, and unable to capture geometries and markings which are difficult to measure or are imperceptible through direct observation due to their faintness.

Fortunately, these issues can now be remedied using numerous recently developed digital techniques which allow for a three-dimensional perspective and offer an accuracy, precision, and level of detail surpassing that of even the most fastidious executions of previous methodologies. This additionally offers the potential for a more thorough and comprehensive analysis of the observed markings using the computational power possible in digital environments which would be prohibitively difficult through physical means. Despite this, the amount of scholarly attention paid to this area of research remains scant and nearly all instances are focused on methodological innovations tested on single timbers or the reconstruction of a site or historic vessel rather than a dedicated investigation of timber surface markings themselves. No publications have attempted to analyze these traces in aggregate for a single site much less compare them across multiple sites.

Using the excavated 18th-century remains of Queen Anne’s Revenge (QAR; ex La Concorde) as a case study, this research takes a step toward the realization of these greater aims. It demonstrates that digital techniques can be particularly efficacious for the aggregate documentation and analysis of surface markings across an archaeological shipwreck site, revealing new information about both the vessel’s historical construction, use, and repair and the archaeological deposition of its remains which is not possible through the examination of isolated examples alone. This new knowledge addresses currently unanswered questions regarding 17th-18th ship construction which are more focused and exact compared to the broader more generalized investigations of the ship’s type and design by tentatively identifying some of the specific individual actions of those that built and sailed La Concorde/QAR. These include the specific means of shaping and fashioning of its timbers, patterns in their fastening, and the identity, sizes, and modes of use of tools employed for those purposes, the documentation of which fills-in current gaps in knowledge not found in other sources and opens up new lines of inquiry as to the reasons behind the methods and tools chosen. It also specifies several types of degradation and alteration to which the remains have been exposed both in situ and during conservation which heretofore have only been described generally. All this is accomplished through the previously untested combination of the complementary strengths of several different digital techniques: Reflectance Transformation Imaging (RTI), close-range photogrammetry, annotation of three-dimensional digital models, and statistical analysis of precise digital and physical measurements. While the collected dataset is too large to accommodate a complete exhibition or theoretical treatment within the length of a master’s thesis, these initial results act as a proof of concept which establishes a foundation for future expanded research. It also determines the level of variation among the markings within a single site of this period and establishes a baseline of signatures of well-documented provenience for future comparison to other shipwreck assemblages which could contribute to the development of their use as a diagnostic trait.