Śatapatha Brāhmaṇa ("of a hundred paths") 2.2.1.16

2.2.1.16

kevalabarhiḥ prathamaṃ havirbhavati | samānabarhiṣī uttare ayaṃvai lokaḥ prathamaṃ havirathedamantarikṣaṃ dvitīyaṃ dyaureva tṛtīyam bahuleva vā iyam pṛthivī lelayevāntarikṣaṃ lelayevāsau dyaurubhe cidenām pratyudyāminī stāmiti tasmātsamānabarhiṣī

The first oblation has a barhis (altar-covering of sacrificial grass) to itself; the two following ones have one barhis in common. Now the first oblation represents this world, the second one that ether, and the third one the sky. But this earth is compact; and the ether and yonder sky are, as it were, trembling: and in order that these two may counterbalance that (earth), the (last) two (oblations) have one barhis in common.