|Abacus. The flat top member of a capital from which the arch springs. Generally sqare in Norman and French Gothic. Generall round in English work from Early English times, sometimes octagonal in Transitional work as at Wells.|
|Abutment. The solid masonry which resists the lateral pressure of a vault or arch.|
|Aisle (Bas-coté, collatcral). The lateral divisions which run parallel with, the nave in a church. Generally one on each side, sometimes two, occasionally on one side only. A three-aisled building is in French called "Un batimentil à trois nefs."|
|Ambo. Pl., Ambones. A raised pulpit from which the Epistle or Gospel was read in early churches.|
|Ambry. Aumbry, Almery (Armoire). Properly any cupboard for keeping sacred vestments or utensils, but generally used in the more limited sense of a niche or cupboard in the wall by the side of the altar in which the altar vessels were kept.|
|Ambulatory. Any place to walk in, but technically used of the curved aisle in a church running round the apse (Déambulatoire), or, in a squarr-ended church, behind the High Altar.|
|Apse. The semicircular or multangular termination of a basilica or church. In Saxon churches found only in the southern type. Usual in Norman times, though few are now to be found in England. Later, replaced by the square east end. The almost invariable termination to a French church.|
|Arcade (Arcature). A series of arches, but generally applied in speaking of mediaeval architecture to a series of small blank arches placed in front of a Wall.|
|Arch. The various forms of arches are named as follows:|
ROUND, or SFMICIRCULAR. Are en plein-cintre.
If the centre is above the impost it is said to be stilted (surhaussé), if below it, segmental (surbaissé). Nearly all French arches are slightly stilted, whereby the optical effect is greatly improved. In England they are much more rarely so.
The Horse Shoe (Arc en fer à cheval). Rarely used except in a few Norman buildings as at Durham and Bernay. So far as possible all the curves in a Norman building were struck with one opening of the compass. Pointed Arch (Are brisé, Arc ogival,1 or Arc en tiers point.).
This last name has conic to be employed in modern French for