Śatapatha Brāhmaṇa ("of a hundred paths") 3.9.3.26

3.9.3.26

atha maitrāvaruṇacamasenaitāmāhutimapaplāvayati | kārṣirasīti yathā vā aṅgāro 'gninā psātaḥ syādevameṣāhutiretayā devatayā psātā bhavati rājānaṃ vā etābhiradbhirupasrakṣyanbhavati yā etā maitrāvaruṇacamase vajro vā ājyaṃ retaḥ somo nedvajreṇājyena retaḥ somaṃ hinasānīti tasmādvā apaplāvayati

Thereupon he makes that oblation (ghee) float away by means of the Maitrâvaruna's cup, with (Vâg. S. VI, 28), 'Thou art furrowing!' Even as a coal is consumed by Fire, so is that oblation consumed by that deity. Now that water, which is in the Maitrâvaruna's cup, he will have to pour on the king (Soma); and ghee being a thunderbolt, and Soma seed, he makes (the ghee) float away lest he should injure that seed, Soma, by that thunderbolt, the ghee.