Lead, salt, cupels, gold, and silver

Meaning

The lead-and-cupel account is voiced first as an imagined objection to Nuysement’s reading of Saturn. The opponent treats Saturn as lead, the oldest metal, whose rawness and abundance of salt explain its biting or devouring action. Gold and silver can be swallowed yet are said to return from the refiners’ cupels because their firmness resists destruction. Nuysement accepts that this interpretation fits some details but argues that his universal-spirit reading fits the whole figure better. Lead, salt, cupels and noble metals therefore have distinct explanatory roles within a partially accepted interpretation, not interchangeable names for the universal subject. The passage is not an assay protocol.