It was divided into several subordinate ranks and classes; and they all depended upon a chief or Arch-Druid, who was elected to his place with great authority and preeminence for life.

They were further armed with a power of interdicting from their sacrifices, or excommunicating, any obnoxious persons.

This interdiction, so similar to that used by the ancient Athenians, and to that since practised among Christians, was followed by an exclusion from all the benefits of civil community; and it was accordingly the most dreaded of all punishments.

This ample authority was in general usefully exerted; by the interposition of the Druids differences were composed, and wars ended; and the minds of the fierce Northern people, being reconciled to each other under the influence of religion, united with signal effect against their common enemies.
There was a class of the Druids whom they called Bards, who delivered in songs (their only history) the exploits of their heroes, and who composed those verses which contained the secrets of Druidical discipline, their principles of natural and moral philosophy, their astronomy, and the mystical rites of their religion.

These verses in all probability bore a near resemblance to the Golden Verses of Pythagoras,--to those of Phocylides, Orpheus, and other remnants of the most ancient Greek poets.