ii. 180;

perfected, i. 147; ribbed, rationale of, 238, 246, 274, 344; to the nave of St. Stephen’s, Caen, ii. 67; Norman, 79, 87; round-arched, 153, 168, 171, 191; of the polygon, 162, 172; of oblong spaces, 163, 177, 205; of aisles passing round a polygonal figure, 164; a circular building with a central pillar, 166, 184; a polygon with a central pillar, 168; stilting, 163-165, 172, 183, 205; moulded ribs to the intersections of, 175; with raised ridges, 171, 176, 186, 218; with level ridges, 177, 183, 186, 209; the _dome_, 168-170; new form of, 171; over wide spaces, 180; triangular spaces, 175; irregular spaces, _ibid._; stilting the wall-ribs in, 187; spaces, surfaces of, 187, 195, 269; octopartite, 196; quinquepartite, 197; decapartite, _ibid._; dodecapartite, _ibid._; of two chapels near the west end, Lincoln, 198; of the crypt, Glasgow, 200; choir, Lincoln, 202; chapter-house, Lichfield, 203; octagonal kitchen, Durham, _ibid._; Caudebec, Lady Chapel, hexagon with pendant, _ibid._; Lady Chapel, Salisbury, 204; presbytery, Ely, 209, bays, west of the crossing, Westminster Abbey, _ibid._; chapter-house and Lady Chapel, Chester, 210; chapter-house, Wells, _ibid._; Exeter Cathedral, 211; cloisters, Westminster Abbey, _ibid._; Liernes, 182, 211-213; Ely Cathedral, 212; Nantwich Church, _ibid._; nave, Westminster, _ibid._; Crosby Hall and Eltham Palace, 213; choir, Gloucester, 214; nave, Winchester, _ibid._; half-height plans of, 216; fan, see Fan-vaulting.

Vaulting-ribs, development of, ii. 191-193, 209; to set out, 192, 193; determining the plans of abaci, 207; repetition of the same curve for the, 216; a curve of two centres for, _ibid._; in fan-vaulting, 217.

Vaults, i. 19, 47; barrel, 51;