Ptolemies, called the Ptolemaic, had hitherto been used, with some
slight alterations; but Copernicus, an eminent astronomer, born at
Thorn, in Polish Prussia, in 1473, adopted the system which had been
taught by Pythagoras in Greece, five or six hundred years before the
time of Ptolemy. About the same time with Copernicus flourished Tycho
Brahe, born in Denmark, 1546.

_Geniuses_, men gifted with superior mental faculties.

_Mental_, belonging to the mind.

_Faculties_, powers of doing anything, whether menial or
bodily; abilities; powers of the mind.

What next greatly forwarded this interesting science?

The introduction of telescopes by Galileo, who by their means
discovered the small stars or satellites which attend the planet
Jupiter; the various appearances of Saturn; the mountains in the Moon;
the spots on the Sun; and its revolution on its axis.

_Satellites_, attendants.

What celebrated Astronomer arose in England?

The immortal Sir Isaac Newton, born in 1642, at Woolsthorpe, in
Lincolnshire, who has, perhaps, contributed more to the advancement of
this science than any one who had before existed. Dr. William
Herschel, a native of Hanover, in Germany, born in 1738, likewise
made many useful discoveries in Astronomy: it was he who first
discovered the seventh primary planet, which he named, in honor of
King George the Third, the Georgium Sidus. George the Third took him
under his especial patronage, and constituted him his astronomer, with
a handsome pension. He resided at Slough, near Windsor, where he died,
in 1822.

_Patronage_, support, favor.

_Constituted_, appointed to any particular office or rank.

_Pension_, yearly allowance of money.

What other circumstance contributed to the advancement of Astronomy?

The increasing perfection of our astronomical instruments,--by means
of which, the most important and interesting discoveries with regard
to the heavens have been made. It is now supposed that the myriads of
the heavenly bodies are all distinct worlds; it is certain, from
observations made by the aid of the telescope, that the moon has its
mountains, valleys, and caverns. One of the greatest astronomers of
our day was the eminent Father Secci.

What are generally meant by the Arts?

Systems of rules designed to facilitate the performance of certain
actions; in this sense, it stands opposed to science. The terms _art_
and _science_ are