ERICSSON, JOHN (1803-1889), Swedish-American naval engineer, was born at Langbanshyttan, Wermland, Sweden, on July 31, 1803. Showing from his earliest years a strong mechanical bent, young Ericsson, at the age of 12, was employed as a draughtsman by the Swedish Canal Company. From 182o to 1827 he served in the army, where his drawing and military maps at tracted the attention of the king, and he soon attained the rank of captain. In 1826 he went to London, at first on leave of absence from his regiment, and in partnership with John Braithwaite con structed the "Novelty," a locomotive engine for the Liverpool and Manchester railway competition at Rainhill in 1829, when the prize, however, was won by Stephenson's "Rocket." The number of Ericsson's inventions at this period was very great. Among other things he worked out a plan for marine engines placed en tirely below the waterline. Such engines were made for the "Victory," for Captain (afterwards Sir) John Ross's voyage to the Arctic regions in 1829, but they did not prove satisfactory. In 1833 his caloric engine was made public.
In 1836 he took out a patent for a screw-propeller, and though the priority of his invention could not be maintained, he was afterwards awarded a one-fifth share of the I20,000 given by the Admiralty for it. At this time Capt. Stockton, of the U.S. Navy, gave an order for a small iron vessel to be built by Laird of Birken head, and to be fitted by Ericsson with engines and screw. This vessel reached New York in May 1839. A few months later Ericsson followed his steamer to New York, and there he resided for the rest of his life, establishing himself as an engineer and a builder of iron ships. In 1848 he was naturalized as a citizen of the United States. Defensive armour for ships of war had long occupied his attentio,,, and he had constructed plans and a model of a vessel lying low in the water, carrying one heavy gun in a circular turret mounted on a turn-table. In 1854 he sent his plans to the French emperor, Louis Napoleon, who declined to use them.
During the American Civil War, the Navy department invited proposals for the construction of armoured ships. Ericsson's design was accepted and the first armoured turret ship, the "Monitor," was launched on Jan. 3o, 1862. On March g, she fought the celebrated action with the Confederate ram "Merri mac."' The peculiar circumstances in which she was built, the great importance of the battle, and the decisive nature of the result gave the "Monitor" an exaggerated reputation, which fur ther experience did not confirm. In later years Ericsson devoted himself to the study of torpedoes and sun motors. He published Solar Investigations (1875) and Contributions to the Centennial Exhibition (1877). He died in New York on March 8, 1889, and in the following year on the request of the Swedish government, his body was sent to Stockholm and thence into Wermland, where, at Filipstad, it was buried on Sept. 15.
A Life of Ericsson by William Conant Church was published in New York in 1890 and in London in