OF WHIRLWINDS.

Anaximander affirms that all these are produced by the wind after this manner: the wind being enclosed by condensed clouds, on account of its minuteness and lightness violently endeavors to make a passage; and in breaking through the cloud gives noise; and the tearing the cloud, because of the blackness of it, gives a resplendent flame.

Metrodorus, that when the wind falls upon a cloud whose densing firmly compacts it, by breaking the cloud it causeth a great noise, and by striking and rending the cloud it gives the flame; and in the swiftness of its motion, the sun imparting heat to it, it throws out the bolt.

The weak declining of the thunderbolt ends in a violent tempest.

Anaxagoras, that when heat and cold meet and are mixed together (that is, ethereal parts with airy), thereby a great noise of thunder is produced, and the color observed against the blackness of the cloud occasions the flashing of fire; the full and great splendor is lightning, the more enlarged and embodied fire becomes a whirlwind, the cloudiness of it gives the hurricane.