that the obelisks which the Egyptians erected served the purpose of gnomons for determining the obliquity of the ecliptic, the altitude of the pole, and the length of the tropical year.  It is thought even that the Pyramids, by the position of their sides toward the cardinal points, attest Egyptian acquaintance with a meridional line.  The Chinese boast of having noticed and recorded a series of eclipses extending over a period of thirty-eight hundred and fifty-eight years; and it is probable that they anticipated the Greeks two thousand years in the discovery of the Metonic cycle,—­or the cycle of nineteen years, at the end of which time the new moons fall on the same days of the year.  The Chinese also determined the obliquity of the ecliptic eleven hundred years before our era.  The Hindus at a remote antiquity represented celestial phenomena with considerable exactness, and constructed tables by which the longitude of the sun and moon were determined, and dials to measure time.  Bailly thinks that thirty-one hundred and two years before Christ astronomy was cultivated in Siam which hardly yields in accuracy to that which modern science has built on the theory of universal gravitation.

But the Greeks after all were the only people of antiquity who elevated astronomy to the dignity of a science.  They however confessed that they derived their earliest knowledge from the Babylonian and Egyptian priests, while the priests of Thebes claimed to be the originators of exact astronomical observations.  Diodorus asserts that the Chaldaeans used the Temple of Belus, in the centre of Babylon, for their survey of the heavens.  But whether the Babylonians or the Egyptians were the earliest astronomers is of little consequence, although the pedants make it a grave matter of investigation.  All we know is that astronomy was cultivated by both Babylonians and Egyptians, and that they made but very limited attainments.  They approximated to the truth in reference to the solar year, by observing the equinoxes and solstices and the heliacal rising of particular stars.

The early Greek philosophers who visited Egypt and the East in search of knowledge, found very little to reward their curiosity or industry,—­not much beyond preposterous claims to a high antiquity, and to an esoteric wisdom which has not yet been revealed.  Plato and Eudoxus spent thirteen years in Heliopolis for the purpose of extracting the scientific knowledge of the Egyptian priests, yet they learned but little beyond the fact that the solar year was a trifle beyond three hundred and sixty-five days.  No great names have come down to us from the priests of Babylon or Egypt; no one gained an individual reputation.  The Chaldaean and Egyptian priests may have furnished the raw material of observation to the Greeks, but the latter alone possessed the scientific genius by which undigested facts were converted into a symmetrical system.  The East never gave valuable knowledge