Faraday to an unidentified correspondent   1 November 1827

Royal Institution | Nov. 1. 1827.

Dear Sir

The minute fragment which I took off from the sonorous plate proves to be a very pure alloy of Copper & Tin there is no lead & only a very minute trace of Iron present[.]

The fragment from the irregularly formed & coarser mass of metal is different in composition in different parts there having been a partial separation of the metal during fusion or else only imperfect mixture in the first instance[.] It is essentially an alloy of copper & tin but it contains a small proportion of lead & a little iron besides[.]

I am dear Sir | Very Truly Yours | M. Faraday