Mullion.—Perpendicular bar between the lights of windows in Gothic architecture.

Nail-headed Moulding.—Moulding in imitation of ornamental nail-heads.

Newell.—The column round which a spiral staircase winds.

Ogee.—A moulding partly concave and partly convex, forming a round and a hollow. Term also applied to an arch formed of contrasted curves.

Orders.—The recesses of a divided arch.

Parvise.—A small room over the porch.

Pilaster.—A pillar, sometimes disengaged but generally attached to a wall.

Piscina.—A basin attached to the wall near the altar of a church, where the priest washed his hands and rinsed the chalice.

Plate-Tracery.—Tracery which appears as if formed by piercing a flat surface with ornamental patterns.

Plinth.—The lowest division of the base of a column, or projecting face at the bottom of a wall.