Archaeological object conservation seeks to preserve the information contained in an object, including materials, technology, evidence of use, and its position in the archaeological record. It also seeks to render the object stable and readable for study and exhibition. Restoration, when discussed as an alternative to conservation, normally implies rendering the object more complete, functional, or aesthetically pleasing.
In the case of complex mechanical objects found in archaeological contexts, there is often an interest on the part of both the general public and cultural heritage professionals alike in rendering the object as complete, and in some cases as functional, as possible. Indeed, it has been argued that the object’s ability to function is an integral part of its nature and should be preserved or recreated. This may be possible in some cases with minimum modification to the object, but the ethical responsibilities of the conservator in preventing damage and loss of information must also be considered.
The clock excavated from the engine room of the Civil War ironclad USS Monitorwhich sank in the Atlantic Ocean in 1862 is an example of the type of object that raises these questions. The Monitor’s clock and its mechanical movement made by Victor Giroud were in excellent condition when brought to the conservation lab of The Mariners’ Museum in 2001, due largely in part to the extensive use of corrosion resistant copper alloys in its construction. As the clock was conserved, it became apparent that steel parts such as the arbors, pinions, and screws had corroded away preferentially resulting in disarticulation of the clock parts during necessary concretion removal.
The excellent condition of the copper alloy parts and the availability of horological experts willing to collaborate on fabrication of replica ferrous parts suggested the possibility that the conserved clock could also be made to run again. While this possibility created a great deal of excitement and interest, it was much closer to restoration, and not entirely compatible with the ethical conservation goals of preserving original material from alteration, wear, and future damage. Close examination of the extant original parts confirmed the possibility that they could be damaged by operating the clock; and though they were in good condition, they had lost some of their structural integrity.
In considering these factors, a middle ground of re-integration of the original components with clearly documented replica parts was decided upon for theUSS Monitor clock. While this did not render the clock functional, it did render it visually complete and allow all of the component parts to be correctly located and supported. As the replacement components are in new condition and are physically marked, confusion with the historic parts is minimized. This re-assembly was also completely reversible, and involved no alteration to the original object.
While it may not be the best approach for all objects with similar concerns, the example of the Monitor’s clock demonstrates that the goals of conservation and visual completeness need not be mutually exclusive.