ARCHITECTURE. 21 



Sacel'lum. — An ornamental chapel witliln a church. 



Saddle-Roof. — A roof having two gables. 



Sash. — A frame for holding the glass of -windows, and so 



formed as to be raised and lowered by means of pulleys. 

 Sciag'raphy (Gr. sA-/a, a shadow, and (/rapho, I write). — The 



profile or vertical section of a building to exhibit its interior 



structure. 

 Shaft. — The body of a column, between the base and the 



capital. 

 Sill. — The horizontal piece at the bottom of a framed case, such 



as that of a door or window. 

 Skew-Back. — The sloping abutment in brickwork or masonry, 



for the ends of the arched head of an aperture. 

 So'cle. — A square member, having a greater breadth than 



height. It is used to support a column, base, etc.. instead 



of a pedestal, from which it differs by having neither base 



nor cornice. 

 Span-Roof. — A roof consisting of two inclined planes, in con- 

 tradistinction to shed or lean-to roofing. 

 Stee'ple. — A turret of a church, ending in a point. 

 Stri'se. — The fillets which separate the furrows or grooves of 



fluted columns. 

 Tam'bour. — The wall of a circular building surrounded with 



columns. 

 Tax'is. — That disposition which assigns to every part of a 



building its just dimensions. 

 To'rus. — A large moulding used in the bases of columns the 



profile whereof is semicircular. 

 Tracery.— That species of pattern-work which is formed or 



traced in the head of a Gothic window by the mullions 



being made to diverge into arches, curves, and flowing 



lines, enriched with foliations. 

 Transom. — A beam across a window, of two lights in height. 



A lintel over a door. 

 Trestle-Work. — A viaduct, pier, or scaffold, resting on numerous 



posts or piles which are usually connected by cross-beams. 

 Truss. — A framed assemblage of timbers for fastening or binding 



a beam, or for supporting a roof, etc. 

 Vault. — An arched ceiling or roof. 

 Venetian Window. — A window formed with three apertures 



separated by slender piers t'rom each otiier, whereof the 



centre one is much larger than those on the sides. 



