OP' THE ELEME N T S O F
the whole building, but interrupted by the means of arches,
particularly in marshy ground : and in the walls of larger
buildings, columns are carried up : a thrifty and useful inven-
tion if winding slairs are placed in them. £
§. 2. There are many kinds of walls: one, which Vitruvius
either names uncertain, or infer ted, I know not which ; it
may be either. Uncertain, or irregular walls, are those (see
Palladio on uncertain slones) where the slones are laid with
their natural dimensions, and their figure and size of course
uncertain. This is explained by Scheme the first, A A.
Perault properly terms that kind of wall infer ted, where the
slones are of a determinate size, and placed in a regular or-
der ; for inslance, in brick work. In this kind of work,
the * rows of Jiones joined together should be alternate, that
the middle slones may be rendered firm and close by those
above them. This rule should take place in the middle of the
wall, if possible, if not, at both the Tides.
The Greeks made their walls in the manner of brick ones,
with a hard slone or ssint of a square form, i. e. of equal
depth and breadth. A wall thus construdted, they called
IcroSo^oc, such is B B. When the slones were irregular
in size, they termed the strudlure ip£v£i<roJ'o[Aog. The third
kind of edisice was called e^TrXeytTov, or involved, D D,
when the slones were even in front, but placed fortuitoussy.
When they filled the middle of the wall internally with
broken or pounded cement, they termed it /’mktuv, E E.
If the walls are ’Itrocio^oi, and fattened together with iron,
they are properly called by Perault, f cramped. See the ex-
ample F F. Aw.tuoS’stov, or net-work strudlure, G G, was
% It is not easy to ascertain the meaning of the Author here. Quaere, whether
he has in view those round turriform ere&ions, at equal intervals, so common
in the walls of our old castles ?
* Coagnientatlones alterr.as, courses of slones.
Corii et Chorii,
fi In the French Language cramponee.