Śatapatha Brāhmaṇa ("of a hundred paths") 6.1.2.19

6.1.2.19

sa yaḥ sa saṃvatsaraḥ prajāpatirvyasraṃsata | ayameva sa vāyuryo 'yam pavate 'tha yā asya tā ṛtavaḥ pañca tanvo vyasraṃsanta diśastṝḥ pañca vai diśaḥ pañcaitāścitayastadyatpañca citīścinoti digbhirevainaṃ taccinoti yaccinoti tasmāccitayaḥ

And that Pragâpati, the year, who became relaxed, is that very Vâyu (wind) who blows yonder. And those five bodily parts of his, the seasons, which became relaxed, are the regions (or quarters); for five in number are the regions, and five those layers: when he builds up the five layers, he builds him up with the regions; and inasmuch as he builds up, therefore they are layers.