(botanist). For Robert Brown (Botanist R.Br.ter) of Caithness , see Robert Brown (explorer) . Robert Brown   Robert Brown in 1855 Born 21 December 1773 Montrose , Scotland Died 10 June 1858 (aged 84) London , England Nationality Scottish Fields Botany Known for Brownian motion Author abbreviation (botany) R.Br. Robert Brown FRSE FRS