ERICSSON, John, American engineer and inventor: b. Wermland, Sweden, 31 July 1803; d. New York, 8 March 1889. He entered the Swedish army in 1820, but resigned in 1826 and soon became known as an inventor. In 1&28 he made the first application to navigation of the principle of condensing steam and returning the water to the boiler ; later he brought out a self-acting gunlock by means of which naval cannon could be automatically discharged at any elevation without regard to the rolling of the ship. In 1833 he designed a caloric engine; and in 1836 invented the screw propellor. He was unable to prove the priority of this in vention, however, and received but one-fifth of the $100,000 which the British Admiralty paid for it In 1839 he supplied engines and screw to the first steam vessel that crossed the Atlantic. The British Admiralty did not be come interested in his inventions, and he came to the United States in 1839 and two years later built the screw-propelling warship Prince ton for the government, the first ship to have her engines and boilers below waterline. This was the pioneer of modern naval construction, and the foundation of the steam madne of the world. The achievement, however, which
made him most famous in the United States was the construction in 1861 of the ironclad Monitor, which was built under a patent granted by the United States government to Theodore Ruggles Timby (q.v.), the inventor of the revolving tur ret, etc; it was launched 100 days after its keel was laid, and arrived in Hampton Roads just in time to defeat, on 9 March 1862, the Confed erate ironclad Merrimac, which had destroyed several wooden warships. A fleet of monitors was soon built and did important service during the remainder of the war. In his later life Ericsson became interested in tor pedoes and in the development of an engine to be worked by solar heat. His remains were taken to Sweden on the cruiser Baltimore, and interred with imposing ceremonies. The centen ary of his birth, 31 July 1903, was observed in New York by the unveiling of a bronze statue of the inventor in Battery Park and in Worces ter, Mass. A magnificent memorial was erected also by his countrymen in Stocldiolm. Con sult his 'Life> by William Conant Church (New York 1890).