[ 79 + ] 
but becaufe errors of workmanfhip, to which they 
are more liable than fquare members, moie fenfioly 
affe£t the magnitude of the foot in fmall meafures, 
than in large ones. . 
Uprights, of any confiderable height, are of lels 
authority than horizontal meafures, from the dif- 
ficulty of taking them correctly ; and being defigned 
by modules, few of them anfwer well to the foot 
meafure. But here we muft except fuch .fhafts of 
columns as are of one block of marble; which feem 
to be as good authority as any part of a building . foi 
the neceffity of making them all exactly of the fame 
length, muft produce accuracy ; and the doing this 
was no difficult piece of workmanfhip. Being like- 
wife commonly (if not always) wrought at the 
quarry, to fave expence in the carriage, they were 
probably befpoke to fome Ample meafure; and we 
(hall find all fuch fhafts anfwer to fome number of 
whole palms. . r 
In the following enquiry, I fuppofe that Defgo- 
detz’s Paris foot contained 1065,4. fuch parts, as 
our London foot contains 1000 : fince it appears, 
from the comparifon of his meafure of the door-cafe 
of the Pantheon with Greaves’s, that if Greaves’s 
London foot was not above 2 parts in 1000 fhorter 
than Graham’s, Defgodetz’s Paris foot was but 
3 of the London foot fhorter than that in the 
archives of the Royal Scociety. This difference (if 
fuch there was) does not amount to the 277th part 
of an inch ; which is much nearer than we can expert 
to find the meafure of the Roman foot, from all the 
remains of antiquity now in being, 
The 
