Mahabharata 9.35.32

9.35.32

pāṃsugraste tataḥ kūpe vicintya salilaṃ muniḥ |
agnīnsaṃkalpayāmāsa hotre cātmānameva ca || 32 ||

Understanding that he had fallen into a pit, his brothers Ekata and Dwita, moved by fear of the wolf as also by temptation, went on, deserting their brother. Thus deserted by his two brothers, who were moved by the temptation of appropriating those animals, the great ascetic Trita, O king, while within that lonely well covered with dust and herbs and creepers, thought himself plunged, O chief of the Bharatas, into hell itself like a sinful wretch. He feared to die inasmuch as he had not earned the merit of drinking Soma juice. Possessed of great wisdom, he began to reflect with the aid of his intelligence as to how he could succeed in drinking Soma even there. While thinking on that subject, the great ascetic, standing in that pit, beheld a creeper hanging down into it in course of its growth. Although the pit was dry, the sage imagined the existence of water and of sacrificial fires there. Constituting himself the Hotri (in imagination), the great ascetic imagined the creeper he saw to be the Soma plant. He then mentally uttered the Richs, the Yayushes and the Samans (that were necessary for the performance of a sacrifice). The pebbles (lying at the bottom of the well) Trita converted into grains of sugar (in imagination). He then, O king, (mentally) performed his ablutions. He conceived the water (he had imagined) to be clarified butter. He allotted to the celestials their respective shares (of those sacrificial offerings).