( io8 ) 
one with another. But to fay, that thofe Gentlemen 
cou’d obferve the Latitude fo nicely, as to find a Dif- 
ference in the Length of the Terredrial Degrees, and 
that only of eleven or twelve Toifes, (when they made 
it the lead) or of thirty-one Toifes, (when they made 
it the mod) is attributing to them an Exa&nefs, fo far 
beyond the Nature of the Inftruments which they 
made ufe of, that it wou’d be rather a Difpraife than a 
Commendation to infid upon it. 
For in the firft Place, the Indrument, with which they 
took Obfervations for the Latitude at the two Ends of 
their Meridian, was a ten Foot Sector (which was worfe 
than that which Monf. Ticard had made Ufe of before, 
becaufe the Telefcope of his Se&or was of ten Foot, 
whereas Monf. CaffinU was but of three Foot, tho’ 
applied to the ten Foot Sedor) where the two hundreth 
Part of an Inch anfwers to eight Seconds of a Degree : 
Now the two hundredth Part of an Inch, being one of 
the lead vifible Parts that we can fee in a divided Line j 
they could not take an Angle nearer than that • nay, 
their Indrument, according to their own Defcnption of 
it was divided but to every twenty Seconds. Now 
they allow, that fixteen Toifes, upon the Surface of the 
Earth anfwer to one Second in the Heavens ^ and they 
don’t pretend to have taken an Obfervation nearer than 
to about three Seconds, which therefore cannot deter- 
mine a Difference lefs than forty eight Toifes; whereas 
the Degrees are only fuppofedto decreafe at mod, thirty 
one Toifes each, from Collioure to Dunkerque. But 
o n Frror of eight Seconds wou’d make a Difference of 
one hundred and twenty eight Toifes, on the Surface of 
the Earth • above ten Times greater tnan the Difference 
of Dearees in the firft Suppofition, and four Tunes 
■Treated than that. Difference in the laft. Befides, the 
f atitude was not obferv’d in the intermediate Places 
