It is not generally known, what has been discovered by men who are the most eminent for their learning, in consequence of their assiduous observations of the heavens, that the fires which fall upon the earth, and receive the name of thunder-bolts, proceed from the three superior stars[254], but principally from the one which is situated in the middle. It may perhaps depend on the superabundance of moisture from the superior orbit communicating with the heat from the inferior, which are expelled in this manner[255]; and hence it is commonly said, the thunder-bolts are darted by Jupiter. And as, in burning wood, the burnt part is cast off with a crackling noise, so does the star throw off this celestial fire, bearing the omens of future events, even the part which is thrown off not losing its divine operation. And this takes place more particularly when the air is in an unsettled state, either because the moisture which is then collected excites the greatest quantity of fire, or because the air is disturbed, as if by the parturition of the pregnant star. CHAP. 19. (21.)—OF THE DISTANCES OF THE STARS. Many persons have attempted to discover the distance of the stars from the earth, and they have published as the result, that the sun is nineteen times as far from the moon, as the moon herself is from the earth[256]. Pythagoras, who was a man of a very sagacious mind, computed the distance from the earth to the moon to be 126,000 furlongs, that from her to the sun is double this distance, and that it is three times this distance to the twelve signs[257]; and this was also the opinion of our countryman, Gallus Sulpicius[258]. CHAP. 20. (22.)—OF THE HARMONY OF THE STARS. Pythagoras, employing the terms that are used in music, sometimes names the distance between the Earth and the Moon a tone; from her to Mercury he supposes to be half this space, and about the same from him to Venus. From her to the Sun is a tone and a half; from the Sun to Mars is a tone, the same as from the Earth to the Moon; from him there is half a tone to Jupiter, from Jupiter to Saturn also half a tone, and thence a tone and a half to the zodiac. Hence there are seven tones, which he terms the diapason harmony[259], meaning the whole compass of the notes. In this, Saturn is said to move in the Doric time, Jupiter in the Phrygian[260], and so forth of the rest; but this is a refinement rather amusing than useful. CHAP. 21. (23.)—OF THE DIMENSIONS OF THE WORLD.