Śatapatha Brāhmaṇa ("of a hundred paths") 6.5.2.3

6.5.2.3

tam prathayati | vasavastvā kṛṇvantu gāyatreṇa candasāṅgirasvadityayaṃ haiṣa loko nidhistametadvasavo gāyatreṇa candasākurvaṃstathaivainamayametadgāyatreṇa candasā karotyaṅgirasvaditi prāṇo vā aṅgirā dhruvāsīti sthirāsītyetadatho pratiṣṭhitāsīti pṛthivyasīti pṛthivī hyeṣa nidhirdhārayā mayi prajāṃ rāyaspoṣaṃ gaupatyaṃ suvīryaṃ sajātānyajamānāyetyetadvai vasava imaṃ lokaṃ kṛtvā tasminnetāmāśiṣamāśāsata tathaivaitadyajamāna imaṃ lokaṃ kṛtvā tasminnetāmāśiṣamāśāste tām prādeśamātrīṃ kṛtvāthāsyai sarvatastīramunnayati

He spreads it out, with (Vâg. S. XI, 58), 'May the Vasus, Aṅgiras-like, fashion thee by the Gâyatrî metre!'--for the bottom part is this (terrestrial) world, and this the Vasus fashioned by means of the Gâyatrî metre; and in like manner does this one now fashion it by means of the Gâyatrî metre;--'Aṅgiras-like,' he says, for Aṅgiras is the breath. 'Thou art steadfast!'--that is, 'thou art firm,' or, 'thou art fixed;'--'Thou art the earth!'--for this bottom part is indeed the earth;--'Establish in me offspring, increase of wealth, lordship of cattle, manhood, clansmen for the Sacrificer!' For the Vasus, having fashioned this (terrestrial) world, invoked this blessing thereon; and in like manner does the Sacrificer, having fashioned this world, now invoke this blessing thereon. Having made it of the measure of a span (in each direction), he then turns up its edge on each side.