Hence a sphere of
one foot in diameter, and of a like nature to the earth, would attract a small
body placed near its surface with a force 20000000 times less than the earth
would do if placed near its surface; but so small a force could produce no
sensible effect. If two such spheres were distant but by 1/4 of an inch, they
would not, even in spaces void
of resistance,come together by
the force of their mutual at-
traction in less than a month's
time; and lesser spheres will
come together at a rate yet
slower, namely in the propor-
tion of their diameters. Nay,
whole mountains will not be
sufficient to produce any sen-
sible effect. A mountain of
an hemispherical figure, three
miles high, and six broad, will
not, by its attraction, draw
the pendulum two minutes out of the true perpendicular; and it is only in
the great bodies of the planets that these forces are to be perceived,

from
Sir Isaac Newton
PRINCIPIA
Vol II: THE SYSTEM OF THE WORLD
Motte's translation revised by Cajori
page 570
University of California Press