Rib vaults appear in English architecture at the end of the eleventh century and by the early part of the next had spread throughout most parts of the country and across the Channel into Normandy. Rib construction was pioneered by the builders of great churches, first apparently at Durham, and was then developed and elaborated at sites such as Winchester, Gloucester, Peterborough, Lessay, Saint-Etienne in Caen, and many others. Although it is impossible to pinpoint the precise moment, by the second quarter of the twelfth century ribs were also being constructed in smaller churches in many areas of England and Normandy. Anglo-Norman parish church masons might construct ribs under towers or in porches, but the majority of survivals are in chancels, where the presence of ribs was clearly the result of a desire to distinguish and embellish the functionally most important and most sacred part of the church. 1 This article is an examination and comparison of the ways parish church masons in England and Normandy designed their rib vaults in the first two-thirds of the twelfth century. 2 Its thesis is simple: ribs engendered a great deal of creative formal thinking among parish church masons by providing them with an expressive and versatile architectural form the use of which could measurably enhance the spatial splendour of their patrons' chancels. The demonstration of this thesis is less simple, however, for it necessarily requires the detailed description, analysis and comparison of many ribvaulted chancels. Moreover, these descriptions are not meant merely as the means to the easily digestible end of generalization. Rather, they are the end -the appreciation of individual designs should be the necessary end of any discussion of architectural aesthetics. Nevertheless, in the interest of clarity and readability I have ordered my discussion around certain issues or questions that each mason had to face or answer when designing a rib-vaulted chancel. While such an approach risks doing violence to the integrity of individual designs, it makes clear the shared formal concerns of the masons building them and the impressive variety (or nuances) they achieved within what might seem, prima facie, a relatively restricted architectural format
THE SPATIAL SETTING AND FUNCTIONAL RATIONALE FOR PARISH CHURCH RIB VAULTSTo reiterate: the vast majority of Romanesque rib vaults in English and Norman parish churches were constructed in chancels. These were almost always aisleless eastern arms of one or two bays. The number of bays was significant, as we shall see, for the possibilities available to the mason constructing a ribbed vault, but that number was no doubt determined by the patron for financial or functional reasons. Many of the rib