Anandakanda 1.23.156

1.23.156

tadūrdhvaṃ piṣṭitulyaṃ ca gandhakaṃ cūrṇitaṃ kṣipet /
nirudhya bhūdhare yantre pācayejjārayetkramāt //

on top of that, one should throw pulverized sulphur equal to the paste.
Having sealed it, one should cook it in a bhūdhara apparatus and digest it systematically.