Lyon Playfair (1818-1898) Scottish chemist and politician. He studied chemistry at Glasgow under Thomas Graham, and under Liebig at Giessen. Professor chemistry at Edinburgh university 1858-1896. Discovered the nitroprusside class of salts. Chemist to the Geological Survey, 1846. Elected a Fellow of the Royal Society 1848. Engaged in the organisation of the Great Exhibition of 1851. Liberal MP for the universities of Glasgow and Edinburgh 1868-1885. Secretary of State for Science and Art 1855. Deputy Speaker of the Hosue of Commons 1880-1883. Knighted 1883. Created Baron 1892. From 'Men of Mark' by Thompson Cooper. (London 1877).