With nitre and vitriol

Meaning

Phrase.

Nitre and vitriol complete the list by which the alchemist asserts his competence in purification. The corrective speaker refuses the inference from this familiar treatment to the wise men’s Mercury. The source’s historical preparation-names do not license fixed modern compositions in every context. Their local function is evidential and comic: they show what the character knows how to name while failing to understand the requested distinction.