Śatapatha Brāhmaṇa ("of a hundred paths") 5.2.1.17

5.2.1.17

āśvattheṣu palāśeṣūpanaddhā bhavanti | sa yadevādo 'śvatthe tiṣṭhata indro maruta upāmantrayata tasmādāśvattheṣu palāśeṣūpanaddhā bhavanti viśo 'nūdasyanti viśo vai maruto 'nnaṃ viśastasmādviśo 'nūdasyanti saptadaśa bhavanti saptadaśo vai prajāpatistatprajāpatimujjayati

They (the pieces of salt) are done up in asvattha (ficus religiosa) leaves: because Indra on that (former) occasion called upon the Maruts staying on the Asvattha tree, therefore they are done up in asvattha leaves. Peasants (vis) throw them up to him, for the Maruts are the peasants, and the peasants are food (for the nobleman): hence peasants throw them up. There are seventeen (bags), for Pragâpati is seventeenfold: he thus wins Pragâpati.