“The sulphur I sold to Mr. Colnaghi for £150, which I thought a low price at the time for such an interesting and unique curiosity, indispensable for illustrating and fixing the date of the invention of the art of engraving (as it is now called). This sulphur, with the print preserved at Paris, and the pax of Finiguerra himself, preserved at Florence, together with the entry in the journal of the Goldsmiths’ Company, also preserved at Florence, showing the date of the completion of the pax to be 1452, form altogether an irrefragable chain of proof which must satisfy the most sceptical. By a memorandum in Seratti’s own handwriting, which is amongst my papers (but having been sent from Bombay to Liverpool, I have not yet got), it appears that he purchased the sulphur from a painter, who bought it with a heap of other trinkets at the stall of a petty dealer in Florence: and on acquiring it Seratti compared it with the pax itself, and ascertained it to be the genuine work of Finiguerra.
“I may add a few observations of my own, not altogether irrelevant to the subject.
“The silver vessel, or pax, generally enclosed some relic, and was kissed by the congregation or other individuals in token of devotion; and the Count Seratti mentions that the one of which this sulphur is in part a facsimile, is very much worn by this repeated act of devoutness. The word pax appears to be a corruption of pyxis, a box; and we have in Shakspeare _a pyx of little value_. The engraving was usually filled up with a metallic mixture of a dark composition, which, being fused by the action of fire, became incorporated with the vessel itself. This process was called Niello, or Anniello, Niellare, or Anniellare; hence our _anneal_, the term probably derived from _nigellum_, or perhaps even from Mêl, the Indian term for _black_, and applied to indigo, by which name that dye was originally known in Europe, and it was probably used in the composition before alluded to. The term _anniello_, and the purpose to which these pyxes were applied, is further illustrative of a passage in Shakspeare, which I believe has hitherto puzzled commentators. It is this:--Hamlet accuses his uncle of having dispatched his father ‘unhousel’d, unanointed, _unanneal’d_;’ it alludes to the custom in Catholic countries of offering relics preserved in their pyxes to be kissed after extreme unction.