And the chief of the deities spent his time seeking out an opening, troubled in mind. And one day, when it was evening, that terrible hour, Indra saw on the shore of the sea the mighty Asura. And he recalled the boon that had been granted to the illustrious Asura, saying: 'This is the terrible evening hour; it is neither day nor night; and this Vritra, my enemy, who has deprived me of everything, must without doubt be killed by me. If I do not slay Vritra, this great and mighty Asura of gigantic frame, even by deceit, it will not go well for me.' And as Indra pondered all this, thinking of Vishnu, he saw at that moment in the sea a mass of foam the size of a hill. And he said: 'This is neither dry nor wet, and it is no weapon; let me hurl it at Vritra.