Mahabharata Anushasna Parva Chapter 85:3

Mahabharata Anushasna Parva (Dana Dharma Parva) Chapter 85:3 Ye shall also be able to wander about at night-time when everything is enveloped in thick darkness." Having said this unto the frogs, the deities once more went over every part of the earth for finding out the deity of blazing flames. In spite of all their efforts, however, they failed to get at him. Then, O perpetuator of Bhrigu's race, an elephant, as large and mighty as the elephant of Sakra, addressed the gods, saying, "Agni is now residing within this Aswattha tree! Incensed with wrath, Agni cursed all the elephants, O descendant of Bhrigu saying, "Your tongues will be bent back." Having been pointed out by the elephants, the deity of fire cursed all elephants even thus and then went away and entered the heart of the Sami tree from the desire of residing within it for some time. Listen now, O puissant hero, what favour was shown unto the elephants, O foremost one of Bhrigu's race, by the deities of unbaffled prowess who were all gratified with the service a representative of their had done them. 'The Deities said, "With the aid of even your tongues bent inwards ye shall be able to eat all things, and with even those tongues ye shall be able to utter cries that will only be indistinct." Having blessed the elephants in this way, the denizens of Heaven once more resumed their search after Agni. Indeed, having issued out of the Aswattha tree, the deity of fire had entered the heart of Sami. This new abode of Agni was divulged by a parrot. The gods thereupon proceeded to the spot. Enraged with the conduct of the parrot, the deity of blazing flames cursed the whole parrot race, saying, "Ye shall from this day be deprived of the power of speech." Indeed, the eater of sacrificial libations turned up the tongues of all the parrots. Beholding Agni at the place pointed out by the parrot, and witnessing the curse denounced upon him, the gods, feeling a compassion for the poor creature, blessed him, saying, "In consequence of thy being a parrot, thou shalt not be wholly deprived of the power of speech. Though thy tongue has been turned backwards, yet speech thou shalt have, confined to the letter K. Like that of a child or an old man, thy speech shall be sweet and indistinct and wonderful." Having said these words unto the parrot, and beholding the deity of fire within the heart of the Sami, the gods made Sami wood a sacred fuel fit for producing fire in all religious rites. It was from that time that fire is seen to reside in the heart of the Sami. Men came to regard the Sami as proper means for producing fire (in sacrifice). The waters that occur in the nethermost regions had come into contact with the deity of blazing flames. Those heated waters, O thou of Bhrigu's race, are vomited forth by the mountain springs. In consequence, indeed, of Agni having resided in them for some time, they became hot through his energy. Meanwhile, Agni, beholding the gods, became grieved. Addressing the deities, he asked them, "What is the reason of your presence here?" Unto him the deities and the great. Rishi said, "We wish to set thee to a particular task. It behoveth thee to accomplish it. When accomplished, it will redound greatly to thy credit."