AMONG the best-known inventors of electrical machines of the last part of the nineteenth century was James Wimshurst, the centenary of whose birth occurs on April 13. The son of Henry Wimshurst (1804–84), the constructor of the pioneer screw-propelled ship Archimedes, Wimshurst was born at Poplar, and after leaving school was apprenticed at the Thames Iron Works, Blackwall, then a well-known shipbuilding yard. At the age of twenty-one years he became a ship surveyor to Lloyd's Register, from 1865 until 1874 was chief of the Liverpool Underwriters' Registry, and then for twenty-five years, 1874–99, was chief shipwright surveyor to the Board of Trade in London. Living at Clapham, he had a good private workshop and for twenty years devoted himself to the improvement and construction of electrical influence machines. The early machines of this type had all sprung from Volta's electrophorus and had been built by Lichtenberg, Bennet, Cavallo, Nicholson, and others, but it was not until the work of Topler (1836–1912) and Holtz and Wimshurst that there was any marked advance in design. The machine with radial strips of tinfoil and contact brushes was described by Holtz in 1881 and again in 1882 and 1883 by Wimshurst, whose improvements were made independently. Altogether he made more than ninety Wimshurst machines. Many of these were presented to hospitals, and two of his very large ones are preserved in the Science Museum. A member of the Physical and Rontgen Societies, and a manager of the Royal Institution, Wimshurst was elected a fellow of the Royal Society in 1898. He died suddenly on Jan. 3, 1903.