the earth, and its axis from east to west.…While the planets, the sun, and the moon describe certain oblique circles comprehended within the Zodiac. Admitting these points in whole or in part, astronomers proceed to treat of other matters [such as] the motions [of the stars], their revolutions, eclipses, size, relative distance, and a thousand similar particulars.…The heavens and the earth must be supposed to be divided each into five zones, the celestial zone to possess the same names as those below.…These zones may be distinguished by circles drawn parallel to the equator on either side of it. Two of these will separate the torrid from the temperate zones, and the remaining two the temperate from the frigid.…Likewise the torrid zone, which is divided into two halves by the equator, is distinguished as having a northern and southern side." In a general way, this is substantially what a modern astronomer would tell us, with the exception that in the old system the earth took the place of the sun, and it is noticeable, that Strabo says, that it is the business of an astronomer to ascertain the size and relative distances of the heavenly bodies.
Several ancient computations of the measures of the universe, claiming to be accurate, have survived to our time. Such as the distances of the planetary orbits recorded by Ptolemy, and the calculation of the earth's circumference made by Eratosthenes. Ptolemy's measurements are very obviously wrong, and curiously enough this seems to be well known to Hippolytus, who, after quoting the figures, thus concludes an ironical passage: "Oh pride of vain-toiling soul, and incredible belief, that Ptolemy should be considered preeminently wise among those who have cultivated similar wisdom" ("Refutation of all Heresies,"
