Oxygen isotope dating of oak and elm timbers from the portcullis windlass, Byward Tower, Tower of London

Researchers successfully dated oak and elm timbers from the portcullis windlass mechanism in the Byward Tower of the Tower of London using a novel oxygen isotope dendrochronology method. The study determined that the oak timbers were felled in winter AD 1656/7, while the associated elm shaft was cut after AD 1648. This is the first application of this technique to date elm, demonstrating its potential for dating non-oak species. The findings build on previous dendrochronological efforts that had failed to date these samples, advancing the use of stable oxygen isotopes in archaeological timber analysis.

Loader, N. J., Miles, D., McCarroll, D., Young, G. H. F., Davies, D., Bronk Ramsey, C., & James, J. G. (2020). Oxygen isotope dating of oak and elm timbers from the portcullis windlass, Byward Tower, Tower of London. Journal of Archaeological Science, 116, 105103. https://doi.org/10.1016/j.jas.2020.105103