LET. II. OF THE EARTH. 2Z

It is not known who was the first that assertedthe figure of the earth to be spherical; but thedoctrine is undoubtedly very ancient. For atthe taking of Babylon by Alexander the Great,eclipses were found to have been set down andcomputed for many centuries before the birthof Christ; which, without a knowledge of theglobular figure of the earth, could not havebeen done. shales the Milesian, who livedabout 600 years before Christ, must likewisehave been sufficiently acquainted with this sub*ject; since, according to the testimony of Hero-dotus, he predicted an eclipse of the sun. " Afterthe war, said he, had been carried on for sixyears between the Medes and Lydians, as theywere going out to battle, the day became pre-sently as dark as the night; which change hadbeen predicted by Thales to the Ionians.”

It appears therefore that, in those early times,the true figure of the earth was not unknownin the world. But it is also equally certain, thatthis knowledge was confined to a few; and thateven some of the greatest poets and mathema-ticians themselves were ignorant of it. ThusHeraclitus, a Greek philosopher, who flourishedabout 500 years before Christ, supposed it tohave the flvape of a skiff or canoe. Anaximan^der, his contemporary, imagined it to be cylin-drical ; and Aristotle, the great oracle of anti-quity, gave it the form of a timbrel.

C 4

These,