Caesar says that the Celtic Juppiter governed heaven.  A god who carries a wheel, probably a sun-god, and another, a god of thunder, called Taranis, seem to have been equated with Juppiter.  The sun-god with the wheel was not equated with Apollo, who seems to have represented Celtic sun-gods only in so far as they were also gods of healing.  In some cases the god with the wheel carries also a thunderbolt, and on some altars, dedicated to Juppiter, both a wheel and a thunderbolt are figured.  Many races have symbolised the sun as a circle or wheel, and an old Roman god, Summanus, probably a sun-god, later assimilated to Juppiter, had as his emblem a wheel.  The Celts had the same symbolism, and used the wheel symbol as an amulet,[78] while at the midsummer festivals blazing wheels, symbolising the sun, were rolled down a slope.  Possibly the god carries a thunderbolt because the Celts, like other races, believed that lightning was a spark from the sun.

Three divinities have claims to be the god whom Caesar calls Dispater—­a god with a hammer, a crouching god called Cernunnos, and a god called Esus or Silvanus.  Possibly the native Dispater was differently envisaged in different districts, so that these would be local forms of one god.

1.  The god Taranis mentioned by Lucan is probably the Taranoos and Taranucnos of inscriptions, sometimes equated with Juppiter.[79] These names are connected with Celtic words for “thunder”; hence Taranis is a thunder-god.  The scholiasts on Lucan identify him now with Juppiter, now with Dispater.  This latter identification is supported by many who regard the god with the hammer as at once Taranis and Dispater, though it cannot be proved that the god with the hammer is Taranis.  On one inscription the hammer-god is called Sucellos; hence we may regard Taranis as a distinct deity, a thunder-god, equated with Juppiter, and possibly represented by the Taran of the Welsh tale of Kulhwych.[80]

Primitive men, whose only weapon and tool was a stone axe or hammer, must have regarded it as a symbol of force, then of supernatural force, hence of divinity.  It is represented on remains of the Stone Age, and the axe was a divine symbol to the Mycenaeans, a hieroglyph of Neter to the Egyptians, and a worshipful object to Polynesians and Chaldeans.  The cult of axe or hammer may have been widespread, and to the Celts, as to many other peoples, it was a divine symbol.  Thus it does not necessarily denote a thunderbolt, but rather power and might, and possibly, as the tool which shaped things, creative might.  The Celts made ex voto hammers of lead, or used axe-heads as amulets, or figured them on altars and coins, and they also placed the hammer in the hand of a god.[81]