Mbh 1.146.2a

“Vaisampayana said, ‘The wicked Duryodhana became very pleased when the king, O Bharata, had said so unto Pandavas. And, O bull of Bharata’s race, Duryodhana, then, summoning his counsellor, Purochana in private, took hold of his right hand and said, ‘O Purochana, this world, so full of wealth, is mine. But it is thine equally with me. It behoveth thee, therefore, to protect it. I have no more trustworthy counsellor than thee with whom to consult. Therefore, O sire, keep my counsel and exterminate my foes by a clever device. O, do as I bid thee. The Pandavas have, by Dhritarashtra, been sent to Varanavata, where they will, at Dhritarashtra’s command, enjoy themselves during the festivities. Do that by which thou mayest this very day reach Varanavata in a car drawn by swift mules. Repairing thither, cause thou to be erected a quadrangular palace in the neighbourhood of the arsenal, rich in the materials and furniture, and guard thou the mansion well (with prying eyes). And use thou (in erecting that house) hemp and resin and all other inflammable materials that are procurable. And mixing a little earth with clarified butter and oil and fat and a large quantity of lac, make thou a plaster for lining the walls, and scatter thou all around that house hemp and oil and clarified butter and lac and wood in such a way that the Pandavas, or any others, may not, even with scrutiny behold them there or conclude the house to be an inflammable one. And having erected such mansion, cause thou the Pandavas, after worshipping them with great reverence, to dwell in it with Kunti and all their friends. And place thou there seats and conveyances and beds, all of the best workmanship, for the Pandavas, so that Dhritarashtra may have no reason to complain. Thou must also so manage it all that none of Varanavata may know anything till the end we have in view is accomplished.