"Obstructor," and the consequent liberation of the waters or the winning of light, forming his mythological essence. This myth furnishes the Rishis with an ever-recurring theme. Armed with his thunderbolt, exhilarated by copious draughts of soma, and generally escorted by the Maruts or Storm-gods, Indra enters upon the fray. The conflict is terrible. Heaven and earth tremble with fear when Indra smites Vṛitra like a tree with his bolt. He is described as constantly repeating the combat. This obviously corresponds to the perpetual renewal of the natural phenomena underlying the myth. The physical elements in the thunderstorm are seldom directly mentioned by the poets when describing the exploits of Indra. He is rarely said to shed rain, but constantly to release the pent-up waters or rivers. The lightning is regularly the "bolt," while thunder is the lowing of the cows or the roaring of the dragon. The clouds are designated by various names, such as cow, udder, spring, cask, or pail. They are also rocks (adri), which encompass the cows set free by Indra. They are further mountains from which Indra casts down the demons dwelling upon them. They thus often become fortresses (pur) of the demons, which are ninety, ninety-nine, or a hundred in number, and are variously described as "moving," "autumnal," "made of iron or stone." One stanza (x. 89, 7) thus brings together the various features of the myth: "Indra slew Vṛitra, broke the castles, made a channel for the rivers, pierced the mountain, and delivered over the cows to his friends." Owing to the importance of the Vṛitra myth, the chief and specific epithet of Indra is Vṛitrahan, "slayer of Vṛitra." The following stanzas are from one of the most graphic of the
