102 
third part, nor more than half its length, unless the na- 
ture of the site prevent it, and impose a different pro- 
portion; if, however, that be longer than necessary, a 
chalcidicum is placed at the extremity, as in the Julian 
basilica on the Aquiline. The columns of basilicæ are 
to be of a height equal to the breadth of the portico, and 
the width of the portico one-third of the space in the 
middle. The upper columns, as herein above described, 
are to be less than those below. The parapet between 
the upper columns should be made one-fourth less than 
those columns, so that those walking on the floor of the 
basilica may not be seen by the merchants. The propor- 
tions of the architrave, frieze, and cornice may be learnt 
from what has been said on columns in the third book. 
Basilicæ, similar to that which I designed and carried into 
execution in the Julian colony of Fano, will not be defi- 
cient either in dignity or beauty. The proportions and 
symmetry of this are as follow. The middle vault, be¬ 
tween the columns, is one hundred and twenty feet long, 
and sixty feet wide. The portico round it, between the 
walls and columns, is twenty feet wide. The height of 
the columns, including the capitals, is fifty feet, their 
thickness five feet, and they have pilasters behind them 
twenty feet high, two feet and a half wide, and one and 
a half thick, supporting beams which carry the floor of 
the portico. Above these, other pilasters are placed, 
eighteen feet high, two feet wide, and one foot thick, 
which also receive timbers for carrying the rafters of the 
portico, whose roof is lower than the vault. The spaces 
remaining between the beams, over the pilasters and the 
columns, are left open for light in the intercolumnia¬ 
tions. The columns in the direction of the breadth of 
the vault are four in number, including those on the an¬ 
gles right and left; lengthwise, in which direction it 
joins the forum, the number is eight, including those at 
the angles; on the opposite side, including all the 
angular columns, there are six columns, because the two