The Covering of the lodge is another, and must be our last reference to this symbolism of the world or the universe. The mere mention of the fact that this covering is figuratively supposed to be "a clouded canopy," or the firmament, on which the host of stars is represented, will be enough to indicate the continued allusion to the symbolism of the world. The lodge, as a representative of the world, is of course supposed to have no other roof than the heavens;[82] and it would scarcely be necessary to enter into any discussion on the subject, were it not that another symbol--the theological ladder--is so intimately connected with it, that the one naturally suggests the other. Now, this mystic ladder, which connects the ground floor of the lodge with its roof or covering, is another important and interesting link, which binds, with one common chain, the symbolism and ceremonies of Freemasonry, and the symbolism and rites of the ancient initiations. This mystical ladder, which in Masonry is referred to "the theological ladder, which Jacob in his vision saw, reaching from earth to heaven," was widely dispersed among the religions of antiquity, where it was always supposed to consist of seven rounds or steps. For instance, in the Mysteries of Mithras, in Persia, where there were seven stages or degrees of initiation, there was erected in the temples, or rather caves,--for it was in them that the initiation was conducted,--a high ladder, of seven steps or gates, each of which was dedicated to one of the planets, which was typified by one of the metals, the topmost step representing the sun, so that, beginning at the bottom, we have Saturn represented by lead, Venus by tin, Jupiter by brass, Mercury by iron, Mars by a mixed metal, the Moon by silver, and the Sun by gold, the whole being a symbol of the sidereal progress of the solar orb through the universe. In the Mysteries of Brahma we find the same reference to the ladder of seven steps; but here the names were different, although there was the same allusion to the symbol of the universe. The seven steps were emblematical of the seven worlds which constituted the Indian universe. The lowest was the Earth; the second, the World of Reexistence; the third, Heaven; the fourth, the Middle World, or intermediate region between the lower and upper worlds; the fifth, the World of Births, in which souls are again born; the sixth, the Mansion of the Blessed; and the seventh, or topmost round, the Sphere of Truth, the abode of Brahma, he himself being but a symbol of the sun, and hence we arrive once more at the masonic symbolism of the universe and the solar orb.