Letter, 'Extrait d'une lettre ecrite a Monsieur Poly par Mr [struck out] 'Extract of a letter written to Mr Poly by Mr [struck out]'. The letter informs Poly that the sender is enclosing specimens from Swedish mines, but does not specify what the specimens are. The letter ends mid-sentence. Subject: Mineralogy Note reads: 'Not to be enter'd' 8 September 1724