Note 217 — Irregular Four-Part Vaulting of Durham Cathedral

Whether these concealed buttresses were first used in Normandy or the Ile-de-France is an open question, but in either case their origin would seem to be traceable to such prototypes as the ramping walls above the transverse aisle arches of such Lombard churches as Sant’ Ambrogio at Milan and perhaps even to Roman monuments like the basilica of Maxentius at Rome. The really important question is to learn when these concealed buttresses were first raised above the aisle roofs to constitute true flying-buttresses. This would seem to have taken place in the Ile-de-France, perhaps at Domont as Porter suggests (Porter, II, pp. 91-92), or at Noyon towards the middle of the twelfth century.