[ 496 ] 
towards the mountain ; and the apparent altitudes of the 
ftars, taken with the inftrument, will be altered accord- 
ingly. 
It Will ealily be acknowledged, that to find a fen- 
lible attradtion of any hill from undoubted experi- 
ment would be a matter of no fmall curiofity, \vould 
greatly illuftrate the general theory of gravity, and would 
make the univerfal gravitation of matter palpable, if 1 
may fo exprefs myfelf, to every perfon, and fit to con- 
vince thofe who will yield their aflent to nothing but 
downright experiment. Nor would its ufes end here; 
as it would ferve to give us a better idea of the total mafs 
of the earth, and the proportional denfity of the matter 
near the furface compared with the mean denfity of the 
whole earth. The refult of fuch an uncommon ex- 
periment, which I fbould hope would prove fuccefsful, 
would doubtlefs do honour to the nation where it was 
made, and the fociety which executed it. 
Sir ISAAC NEWTON gives us the firfi: hint of fuch an 
attempt, in his popular Treatife of the Syftem of the 
World, where he remarks, That a mountain of an he- 
“ mifpherical figTire, three miles high and fix broad, will 
not, by its attradlioii, draw the plumb-line two minutes 
“ out of the perpendicular.” it will appear, by a very 
eafy calculation, that fuch a mountain wuuld attradl the 
plumb-line 1 8 ^' from the perpendicular. 
But the firfi; attempt of this kind was made by the 
French Academicians, w'ho meafured three degrees of 
the meridian near Quito in Peru, and who endeavoured 
to find the elFecfi; of the attraction of Chimborazo, a 
5 mountain 
