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meafures of the degrees of the meridian much more than 
we find they do; and the variation of gravity in different 
latitudes in going from the equator to the poles, as found 
by pendulums, would not he near fo regular as it has 
been found by experiment to be. 
4. The denlity of the fiiperfidal parts of the earth, 
being, however, fufiicient to produce fenhble deflections 
in the plumb-lines of affronomical inftruments, will 
thereby caufe apparent hiequalities in the menfurations 
of degrees in the meridian; and therefore it becomes a 
matter of great importance to chufethofe places for mea- 
furing degrees, where the irregular attradfions of the ele- 
vated parts may be fmall, or in fome meafure compenfate 
one another ; or elfe it will be neceflary to make allov - 
ance for their efiedls, which cannot but be a work of 
great difficulty, and perhaps liable to great uncertainty. 
After all, it is to be wiflied, that other experiments of 
the like kind with this were made in various places, at- 
tended with different circumftances. We feldom acquire 
full fatisfadtion from a Angle experiment on any fubjedt. 
Some may doubt, whether the denflty of the matter near 
the furface of the earth may not be fubjedt to conAdera- 
ble variation ; though perhaps, taking large maffes toge- 
ther, the denflty may be more uniform than is commonly 
imagined, except in hills that have been volcanos. The 
mountain Schehallien, however, bears not any appear- 
ance of having ever been in that ftate ; it being extremely 
folid and denfe, and feemingly compofed of an intire 
rock. 
