According to the common opinion of the Arabs (an opinion sanctioned by the Ḳur-án, and by assertions of their Prophet, which almost all Muslims take in their literal sense), there are Seven Heavens, one above another, and Seven Earths, one beneath another; the earth which we inhabit being the highest of the latter, and next below the lowest heaven. The upper surface of each heaven, and that of each earth, are believed to be nearly plane, and are generally supposed to be circular; and are said to be five hundred years' journey in width. This is also said to be the measure of the depth or thickness of each heaven and each earth, and of the distance between each heaven or earth and that next above or below it. Thus is explained a passage of the Ḳur-án, (ch. lxv. last verse), in which it is said, that God hath created seven heavens and as many earths, or stories of the earth, in accordance with traditions from the Prophet.[14]--This notion of the seven heavens appears to have been taken from the "seven spheres;" the first of which is that of the Moon; the second, of Mercury; the third, of Venus; the fourth, of the Sun; the fifth, of Mars; the sixth, of Jupiter; and the seventh, of Saturn; each of which orbs was supposed to revolve round the earth in its proper sphere. So also the idea of the seven earths seems to have been taken from the division of the earth into seven climates; a division which has been adopted by several Arab geographers.--But to return to the opinions of the religious and the vulgar. Traditions differ respecting the _fabric_ of the seven heavens. In the most credible account, according to a celebrated historian, the first is described as formed of emerald; the second, of white silver; the third, of large white pearls; the fourth, of ruby; the fifth, of red gold; the sixth, of yellow jacinth; and the seventh, of shining light.[15]