K/PP107/11/1/22
Dated 1852-1870. From Scientific apparatus, musical instruments and telegraph equipment, [1834-1875].
Three cryptographs devised by Wheatstone including one wooden prototype with letters and numerals on circular cards attached to a square wooden base; two in original cases with nickel-silver dials, hands and circular removable cards for assigning the code. The dials are inscribed ‘The Cryptograph, C. Wheatstone Invr.’. Cipher post designed by Wheatstone, consisting of a small brass post with rings of letters and numerals on a mahogany base.