=Ambulatory=, a place to walk in. At Westminster the passage round the outside of the Chapel of St. Edward. p. 26. =Arcade=, a series of arches, supported by columns, either open or closed with masonry. Frequently used for the decoration of the walls of churches, on the exterior and interior. p. 13. =Baptistery=, the part of a church containing the font. p. 33. =Boss=, an ornament placed at the intersection of the ribs in vaulted roofs. p. 106. =Breviary=, the book containing the daily service of the Roman Catholic Church. p. 128. =Buttress=, a projection from a wall to give extra strength and support. The _flying buttress_, or _Arc-boutant_ is carried across by an arch from one wall to another. p. 13. =Chalice=, the cup used at the celebration of the Eucharist. p. 28. =Chantry=, a sepulchral chapel, in which masses for the dead were chanted. p. 24. =Choir=, the chancel of collegiate or cathedral churches. p. 32. =Clerestory=, (old spelling clear-story) the upper story or row of windows in a Gothic Church. p. 15. =Cloisters=, covered galleries of communication between the different parts of a monastic building or college. They generally have roofs of groined stone. At Westminster they run round the two quadrangles of the Great and Little Cloisters, and join them together by long stone passages. p. 33. =Crocket=, detached flowers or bunches of foliage, used to decorate the angles of spires, pinnacles and gables. p. 115. =Gable=, the upright triangular piece of masonry or woodwork at the end of a roof. =Gargoyle=, a projecting stone water-spout in the shape of some monster, or the figure of a man from whose mouth the water runs. p. 13. =Gothic= Architecture is chiefly distinguished by the _pointed arch_. It is divided into three periods. The Early English, which prevailed during the thirteenth century. The Decorated style, which prevailed during the fourteenth century. And the Perpendicular, or style of the fifteenth century. In France the latest Gothic style is called Flamboyant. p. 115. =Mullions=, upright bars of stone between the lights of a window. =Nave=, the principal or central division of a Gothic Church, extending from the west end to the entrance of the Choir. p. 64. =Oriel=, a window projecting from the face of the wall, frequently resting on brackets. =Pendant=, a sculptured ornament hanging from a Gothic roof. In the latest or Perpendicular style the pendants are sculptured in the most delicate manner and form the Keystones of the roof, taking the place of the bosses. p. 106. =Pier-Arches=, arches supported on piers (or pillars) between the centre and side aisles. p. 110. =Pyx=, a gold or silver circular vessel in which the Eucharistic wafer was reserved before the Reformation for communicating the sick. The term is also used sometimes, for a casket in which relics are kept; or for boxes in which deeds are preserved. p. 22. =Reredos=, the screen at the back of the Altar. p. 15.