ROBERT BROWN. - Botanist, b. at Montrose in Scotland in 1773, d. in London in 1858, son of a Protestant bishop. He studied medicine at Edinburgh under Rutherford. He was appointed assistant surgeon in a garrison regiment in northern Ireland, where he remained until the end of the year 1800, devoting himself also to botanical studies. About this time he became acquainted with Sir Joseph Banks (b. 1743, d. 1820), another distinguished English naturalist, who had taken part in several voyages including that of Cook’s first circumnavigation of the globe (1768–71), from which he had brought back notable collections. Through Banks’s influence, B. was sent in 1802 on an English expedition to explore the coasts of Australia. There he examined the flora of New South Wales, Tasmania, the islands of Bass Strait, etc.; in 1805 he returned to England with a collection of 4,000 species of plants.
Soon afterward he was appointed librarian of the Linnean Society. He published an account of his observations in *Prodromus florae Novae Hollandiae* (1810), *General remarks geographical and systematical on the botany of Terra australis* (1814), and *Supplementum primum florae Novae Hollandiae*. He also described the plants collected in Java by Horsfield, in Abyssinia by Salt, the collections gathered by Houdney, by Clapperton, by Captain Tuckey, and finally those of Ross, Parry, and Richardson, explorers of Arctic regions. He published numerous papers on pollen and the fertilization of orchids and asclepiads, on fertilization and the development of pollen and ovules in conifers and cycads, on floral morphology, and other topics in anatomy and physiology. He discovered the nucleus in plant cells; in 1827 he was the first to observe under the microscope that characteristic movement of purely physical nature which was later named in his honor as Brownian motion. This movement can be observed with the ultramicroscope in a colloidal solution, and is due to the mutual impact of the molecules of the dispersed substance on those of the dispersing medium, but it can also be seen under the microscope with larger particles.
B. was elected a Fellow of the Royal Society of London in 1811. In 1823 he took possession of Banks’s library and herbarium. He donated his plant collection to the British Museum, which in 1827 appointed him director of its botanical section. In 1832 he received the degree of Doctor from the University of Oxford, and the following year he was admitted to the Academy of Sciences in Paris.
Humboldt rightly called him the “Prince of Botanists.”