A Masterly Hand / Scientia Artis 9

that the works were carved between these dates; such results must be inter- preted. Indeed, dendrochronological study of sculpture encounters difficulties ensuing from the constraints on the artist when working the wood. These relate to wood removed while preparing and carving, and the lapse of time between the felling of the tree and the use of its wood. Wood Removed in the Production Process Dendrochronology dates all the rings present in the wood analysed, and as a result the date obtained for the most recent ring measured provides informa- tion about the felling period of the tree. This period is determined more or less precisely, depending on the preservation of bark and sapwood in the sculp- t ure. 21 If the complete sapwood is preserved up to the cambium (to the bark, fig. 8.10 -A), 22 th e sculpture contains the last ring in the life of the tree. The date of this last ring thus corresponds to the felling date. If only part of the sapwood is present (fig. 8.10-B), the number of missing sapwood rings can be estimated within a range based on statistics recorded on trees of comparable age and provena nce. 23 C onsequently, dendrochronology provides an estimation of the felling date of the tree, to within a few years. Finally, if no sapwood remains, there is no way of determining the number of heartwood rings lost in addition to the sapwood (fig. 8.10-C/D). In these conditions, the date of the last ring measured represents a terminus post quem for felling, that is a date after which the tree was felled. For sculptures, the last situation – a total absence of sapwood – is the most commonly encountered. Sapwood is fragile and readily decomposes. It is therefore unsuitable for sculptures because it affects their durability. Yet some- times part of the sapwood remains. In the Elsloo group, several works have A B C D Fig. 8.10 Transverse section of an oak trunk with the possible positions of the sculptures influencing the dendrochronological interpretation of the felling date: base with complete sapwood (up to the bark, A), base with partial sapwood (B), base without sapwood (only sapwood is missing in C; all sapwood and some heartwood rings are missing in D) Fig. 8.11a-b St Lucy, Siersdorf, Church of St John the Baptist, presence of sapwood on the widest parts of the mantle, on either side of the sculpture 8.10 8.11 b 8.11 a