ancient Hindoos regarding the movements of the sun and moon in
their cycles of nineteen and six hundred years--the Metonic
cycle, and the Neros--proves that long before the birth of
Hipparchus the length of the year was known with a degree of
exactitude which that astronomer had not the means of
determining. It is positively asserted by astronomers that at
least twelve hundred years were required, "during which time the
observations must have been taken with the greatest care and
regularly recorded," to arrive at the knowledge necessary for the
invention of the Neros, and that such observations would have
been impossible without the aid of the telescope.
On the subject of the great learning of an ancient race, Sir W.
Drummond says:
"The fact, however, is certain, that at some remote period there
were mathematicians and astronomers who knew that the sun is in
the centre of the planetary system, and that the earth, itself a
planet, revolves round the central fire;--who calculated, or like
ourselves attempted to calculate, the return of comets, and who
knew that these bodies move in elliptic orbits, immensely
elongated, having the sun in one of their foci;--who indicated
the number of the solar years contained in the great cycle, by
multiplying a period (variously called in the Zend, the Sanscrit,
and the Chinese ven, van, and phen) of 180 years by another
period of 72 years;--who reckoned the sun's distance from the
earth at 800,000,000 of Olympic stadia; and who must, therefore,
have taken the parallax of that luminary by a method, not only
much more perfect than that said to be invented by Hipparchus,
but little inferior in exactness to that now in use among the
moderns;--who could scarcely have made a mere guess when they
fixed the moon's distance from its primary planet at fifty-nine
semi-diameters of the earth;--who had measured the circumference
of our globe with so much exactness that their calculation only
differed by a few feet from that made by our modern
geometricians; --who held that the moon and the other planets
were worlds like our own, and that the moon was diversified by
mountains and valleys and seas;--who asserted that there was yet
a planet which revolved round the sun, beyond the orbit of
Saturn;--who reckoned the planets to be sixteen in number; --and
