This post is strictly for ultra-nerds of Gothic architecture. I recently got this photo of the ‘transitional flying buttress’ between the nave and choir of Chartres Cathedral – something that is not at all easy to do, as the buttress is not visible from the ground but requires access to the cathedral roof. I’d gone up there for other purposes (a Nova documentary on Gothic churches), and so sadly hadn’t come properly prepared to take photos – this one is from my mobile phone, and so is not of high resolution. But I want to put it up here in case anyone else should ever want to use it without the hassle of getting permission to go up on the roof. The structure is significant because it challenges the idea that the nave is older than the choir. The arches of the nave flyers are in a more squat and massive style, with rounded arches, which could be taken as a sign that they were built first, perhaps by a different master, with the slender pointed arches of the choir flyers (more ‘Gothic’, one might say) being added by a later hand. That was the case argued by Louis Grodecki in the 1950s. But this sole ‘transitional’ flying buttress on the east of the transepts seems to be an attempt to merge the different styles of the nave and choir, as though this was part of the plan all along – perhaps, as Jan van der Meulen suggests, the crossing and transepts were built first, and both the nave and choir built out from them at much the same time. All this is discussed in my book Universe of Stone.