Before the vital energy of Varuna was thrown into the pot Mitra discharged his own on Urvasi's account which was the source of Agastya's birth. (Into the pot in which Mitra's energy was discharged Varuņa also put his own and both the energies were mixed up).
तद्धि तेजस्तु मित्रस्य उर्वश्याः पूर्वमाहितम्। तस्मिन्समभवत्कुम्भे तत्तेजो यत्र वारुणम्॥