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If the Roman buildings were correCtly executed, 
and we had the true dimenfions of their feveral parts 
in any known meafure, fome divifors confiding of 
Roman feet, and parts of thofe feet, applied to thefe 
meafures, mud, in the fame building, give the fame 
quotient to all ; and this quotient will be the meafure 
of the foot, by which that building was condruCted, 
in parts of the known meafure. Therefore, where 
a range of dmple divifors, applied to the principal 
parts of any building, give as nearly the fame quo- 
tient as can be expected from the common inaccu- 
racies of workmandiip, we may reafonably conclude, 
that thefe divifors were the architects numbers ; and 
the foot derived from them, that by which the build- 
ing was condruCted. 
As an architect cannot be fuppofed to be limited to 
a few digits in the extent of the front, or of the depth 
of large buildings, it is probable fuch meafures con- 
dded of whole feet. Thefe, and the diameters of cir- 
cular buildings, I call prime meafures. 
In all large prime meafures, the preference is to 
be given to a round number for the divifor; as it is 
more probable a building diould be defigned for i oc 
feet in front, than for pp or ioi : and becaufe the 
paffus was 5 feet, I reckon any multiple of 5 a round 
number. 
The diameters of columns are of lefs authority 
than any other horizontal meafures ; not only on ac- 
count of the difficulty of meafuring them correCtly, 
They both mention the duodecimal divifion, which Teems to have 
been ufed by the vulgar; for the Romans divided every integer into. 
12 uncice. 
but. 
