Shatapatha Brahmana 11.1.6.22

11.1.6.22

atha dakṣiṇāṃ diśamapaśyan tāṃ dakṣiṇāmevākurvata seyaṃ dakṣiṇaiva diktasmādu dakṣiṇata eva dakṣiṇā upatiṣṭhante dakṣiṇato'bhyavājanti dakṣiṇāṃ hyetāmakurvatopaināmitaḥ kurvīmahīti taṃ lokamakurvatemaṃ khalu lokam paśyemeti tadidamantarikṣamabhavadeṣa vai lokaḥ sā yathā haiveyam pratiṣṭhāvirasmiṃloke pṛthivyevamu haivaiṣā pratiṣṭhāviramuṣmiṃloka idamantarikṣaṃ sa yadiha sannamuṃ lokaṃ na paśyati tasmādāhuḥ paro'kṣamasau loka iti

They then beheld the southern quarter, and made it the southern quarter; and it now is that southern (right, dakshinâ) quarter: whence the dakshinâ (cows) stand to the south (of the altar), and are driven up from the south, for they made that the southern one (dakshinâ). 'Let us improve it from here!' they said, and made it to be space. 'May we see this space!' they said; and it became this air, for that (air) is space; for even as the resting-place here in this world is clearly the earth, so the resting-place there in yonder world is clearly this air; and because, whilst being here on earth, one does not see that space, therefore people say, 'That space (or, yonder world) is invisible.'