( 9 6 3>6 
[ 8 I9 3 
The fhafts of the columns, each of 
one block, meafure 35 feet iiy- 
inches, = 38302,6 39|) • • • 
The whole column is 43 feet 6^-inches, 
= 46359,7 48) . . . (965,8 
Thefe are the principal meafures in this building, 
and a mean taken from all of them, except the dia- 
meter of the veftibule, gives a foot of 964,1 London 
parts. 
But the three fmall meafures, of f, 6, and 3 Ro- 
man feet (the firft of which is the paffus) are alone 
fufficient to difcover the meafure of the foot by which 
this building wa? conftruCted. For, being fo often 
repeated with fo little variation, they mull afford a 
mean very near the truth, if their divifors be rightly 
affumed 5 and that thefe are fo, can hardly be doubted. 
For, were the two largelf to be encreafed but by a 
fingle digit, they would give different meaiures of 
the foot from each other ; and that from the paffusf 
fo encreafed, would fall fhort of 952 London parts; 
which is lefs than the leaft of the antient foot-rules. 
On the other hand, were they diminifhed by the 
fame quantity, they would not agree together fo 
nearly in the meafure of the foot as they now do, 
nor give fuch a meafure of it as the reft of the build- 
ing will anfwer to by probable divifors. Befides, I 
have here reckoned only fuch of thefe meafures as 
Defgodetz has figured on his plan ; whereas they are 
much oftener repeated, and that not in the diameters 
of columns, or the members of an order, but in 
tyeaks, projections, and thicknefies of walls, where 
a digit or two more or lefs could make no vifible 
Vol, LI. £ N difference. 
& 
