Anandakanda 1.4.461

1.4.461

mūṣāgarbhe kṣipet tattatpūrvanāgaṃ dhamet tataḥ /
drutaṃ yāvat samuddhṛtya liptvā mūṣāṃ punar dhamet //

One should cast that aforesaid lead into the interior of a crucible and then blow it;
as soon as it is melted, taking it out and smearing the crucible, one should blow it again.