Metrology and proportion in the window tracery of medieval Ireland : an empirical study of Ormond and Connaught

Abstract

This study developed a methodology to investigate whether evidence could be found for the application of systems of proportion and metrology to the design of late medieval window tracery in Ireland. Source data was collected for over two-hundred windows, across three medieval kingdoms, using the three-dimensional measurement technique of stereo photogrammetry. Measurements of window width and height, light width and height, mullion width, tracery field height, and arch span were extracted for each window. Two full building investigations were made using terrestrial laser scanning to generate three-dimensional ground plans and models of a range of architectural details. Measurements from the windows, plans, and details were interrogated using a set of Visual Basic for Applications macros in Microsoft Excel to indicate the preferred unit(s) of measurement and any evidence of the presence of defined ratios between significant features.