Śatapatha Brāhmaṇa ("of a hundred paths") 9.3.1.7

9.3.1.7

atha mārutānjuhoti | prāṇā vai mārutāḥ prāṇānevāsminnetaddadhāti vaiśvānaraṃ hutvā śiro vai vaiśvānaraḥ śīrṣaṃstatprāṇāndadhāti

He then offers the (cakes) to the Maruts;-- the Maruts’ (cakes) are the vital airs: he thus puts the vital airs into him (Agni). [He does so] after offering the Vaisvânara; for the Vaisvânara is the head: he thus puts vital airs into the head.