Horses also signify fire and light. The fiery horses of Helios are an example. The horses of Hector are called Xanthos (yellow, bright), Podargos (swift-footed), Lampos (shining) and Aithon (burning). A very pronounced fire symbolism was represented by the mystic Quadriga, mentioned by Dio Chrysostomus. The supreme God always drives his chariot in a circle. Four horses are harnessed to the chariot. The horse driven on the periphery moves very quickly. He has a shining coat, and bears upon it the signs of the planets and the Zodiac.[589] This is a representation of the rotary fire of heaven. The second horse moves more slowly, and is illuminated only on one side. The third moves still more slowly, and the fourth rotates around himself. But once the outer horse set the second horse on fire with his fiery breath, and the third flooded the fourth with his streaming sweat. Then the horses dissolve and pass over into the substance of the strongest and most fiery, which now becomes the charioteer. The horses also represent the four elements. The catastrophe signifies the conflagration of the world and the deluge, whereupon the division of the God into many parts ceases, and the divine unity is restored.[590] Doubtless the Quadriga may be understood astronomically as a _symbol of time_. We already saw in the first part that the stoic representation of Fate is a fire symbol. It is, therefore, a logical continuation of the thought, when time, closely related to the conception of destiny, exhibits this same libido symbolism. Brihadâranyaka-Upanishad, i: 1, says: “The morning glow verily is the head of the sacrificial horse, the sun his eye, the wind his breath, the all-spreading fire his mouth, the year is the belly of the sacrificial horse. The sky is his back, the atmosphere the cavern of his body, the earth the vault of his belly. The poles are his sides, in between the poles his ribs, the seasons his limbs, the months and fortnights his joints. Days and nights are his feet, stars his bones, clouds his flesh. The food he digests is the deserts, the rivers are his veins, the mountains his liver and lungs, the herbs and trees his hair; the rising sun is his fore part, the setting sun his after part. The ocean is his kinsman, the sea his cradle.”