Matsyapurana 126.44

126.44

haritairavyathaiḥ piṅgair īśvarair brahmavādibhiḥ
bāhyato 'nantaraṃ caiva maṇḍalaṃ divasakramāt //

The Sun in course of one single day and night goes swiftly over the world consisting of the seven oceans and the seven islands, seated in His one-wheeled chariot and drawn by seven horses. The seven horses yoked to the Sun's chariot are no other than the seven chhandas (metres); they can assume forms at their will; they go as they like; their speed is swift as wind; their colour is tawny; and being once yoked they go on incessantly; they never get tired a bit. They are the gods declaring the glory of Brahma. Ascending on such a chariot the Sun travels the earth in course of one day (24 hours.) The horses were yoked at the beginning of Kalpa and carry on the Sun till the end of the Great Dissolution (Mahâ Pralaya). Thus He goes on round and round, day and night, surrounded by the Vâlakhillya Munis. The great Rishis recite praises to Him in the chosen words composed by them; the Gandarbhas and Apsarâs sing and dance round Him. Thus the Sun is carried on by the horses flying like birds. Similarly, the Moon moves on in the several asterisms that are divided into several vîthîs.—41-46.