Shatapatha Brahmana 10.4.5.2

10.4.5.2

śāṭyāyaniru ha smāha saṃvatsara evāgnistasya vasantaḥ śiro grīṣmo dakṣiṇaḥ pakṣo varṣā uttaraḥ śaradṛturmadhyamātmā hemantaśiśirāvṛtū pucam pratiṣṭhā vāgagniḥ prāṇo vāyuścakṣurādityo manaścandramāḥ śrotraṃ diśa āpo mithunaṃ tapaḥ pratiṣṭhā māsāḥ parvāṇyardhamāsā nāḍyo'horātrāṇi rajatasuvarṇāni patrāṇi sa evaṃ devānapyetīti saṃvatsaro'gnirityu haiva vidyādetanmayo bhavatīti tveva vidyāt

And Sâtyâyani said, 'Agni is no other than the Year; his head is the spring, his right wing the summer, his left wing the rainy season, his middle body (trunk) the autumn season, and his tail and feet the winter and dewy seasons--Agni is speech, Vâyu breath, the sun the eye, the moon the mind, the quarters the ear, the generative power water, the feet (and tail) fervour, the joints the months, the veins the half-moons, the silver and gold feathers the days and nights: thus he passes over to the gods.' Let him know, then, that Agni is the Year; and let him know that it is thereof he consists.