The last of the Vedas, Atharva Veda, is completely different from the other three Vedas and composed by two clans of fire priests known as the Bhrigus or the Atharvans and
Angirasas. It also contains compositions of certain other Indo-Aryan clans such as the Kaushikas, Vasishthas and Kashyapas. It derives its name from Atharvan who made a significant contribution in the composition of Atharva Veda. The main theme of Atharva is holy magic and contains magical spells and incantations to appease demons, and curse enemies. It contains about six thousand verses forming 731 poems and a small portion in prose. It also contains materials from the Rig Veda. This text of magic formulae deals with the advanced scientific description of medicines, anatomy and physiology and glorifies the curative powers of herbs and waters which drive diseases away.