Other deities who were similarly exalted as "high heads" at various centres and at various periods, included Anu, Bel Enlil, and Ea, Merodach, Nergal, and Shamash. A symbol of the first three was a turban on a seat, or altar, which may have represented the "world mountain". Ea, as "the world spine", was symbolized as a column, with ram's head, standing on a throne, beside which crouched a "goat fish". Merodach's column terminated in a lance head, and the head of a lion crowned that of Nergal. These columns were probably connected with pillar worship, and therefore with tree worship, the pillar being the trunk of the "world tree". The symbol of the sun god Shamash was a disc, from which flowed streams of water; his rays apparently were "fertilizing tears", like the rays of the Egyptian sun god Ra. Horus, the Egyptian falcon god, was symbolized as the winged solar disc. It is necessary to accumulate these details regarding other deities and their symbols before dealing with Ashur. The symbols of Ashur must be studied, because they are one of the sources of our knowledge regarding the god's origin and character. These include (1) a winged disc with horns, enclosing four circles revolving round a middle circle; rippling rays fall down from either side of the disc; (2) a circle or wheel, suspended from wings, and enclosing a warrior drawing his bow to discharge an arrow; and (3) the same circle; the warrior's bow, however, is carried in his left hand, while the right hand is uplifted as if to bless his worshippers. These symbols are taken from seal cylinders. An Assyrian standard, which probably represented the "world column", has the disc mounted on a bull's head with horns. The upper part of the disc is occupied by a warrior, whose head, part of his bow, and the point of his arrow protrude from the circle. The rippling water rays are V-shaped, and two bulls, treading river-like rays, occupy the divisions thus formed. There are also two heads--a lion's and a man's--with gaping mouths, which may symbolize tempests, the destroying power of the sun, or the sources of the Tigris and Euphrates. Jastrow regards the winged disc as "the purer and more genuine symbol of Ashur as a solar deity". He calls it "a sun disc with protruding rays", and says: "To this symbol the warrior with the bow and arrow was added--a despiritualization that reflects the martial spirit of the Assyrian empire".[368]