197. The small apparent motion of the Stars § 113, discovered by that
great Astronomer, he found to be no ways owing to their annual Parallax
(for it came out contrary thereto) but to the Aberration of their light,
which can result from no known cause besides that of the Earth’s annual
motion; and as it agrees so exactly therewith, it proves beyond dispute
that the Earth has such a motion: for this Aberration compleats all it’s
various Phenomena every year; and proves that the velocity of star-light
is such as carries it through a space equal to the Sun’s distance from
us in 8 minutes 13 seconds of time. Hence, the velocity of light is
[51]10 thousand 210 times as great as the Earth’s velocity in it’s
Orbit; which velocity (from what we know already of the Earth’s distance
from the Sun) may be affected to be at least between 57 and 58 thousand
miles every hour: and supposing it to be 58000, this number multiplied
by the above 10210, gives 592 million 180 thousand miles for the hourly
motion of light: which last number divided by 3600, the number of
seconds in an hour, shews that light flies at the rate of more than 164
thousand miles every second of time, or swing of a common clock
pendulum.