Sir William George Armstrong, an English engineer and inventor, born at Newcastle-upon-Tyne, Nov. 26, 1810. He was educated at Bishop-Auckland, and early busied himself with experiments in the physical sciences, the construction of models, etc. At his father's wish he began the study of law, though he had no inclination for that profession; he passed successfully through his preliminary studies, and became a partner in the firm with which he had been placed. But he devoted all his leisure to mechanical pursuits, and in 1838 produced his first invention, an important improvement in the hydraulic engine; and in 1845 he invented a hydraulic crane, which immediately proved one of the most useful machines of its kind. In 1842 he invented a machine for the production of electricity from steam. Mr. Armstrong was made a member of the royal society in 1846, and in the same year was one of a company to establish the Elswick iron works, at which his cranes are manufactured, with large engines, iron bridges, etc. In 1854, during the Crimean war, the attention of Mr. Armstrong was attracted to improvements in ordnance, and somewhat later he produced the plan of the breech-loading cannon which bears his name.

For this and his other inventions he was knighted in 1859. The construction of iron-clad ships of war led him to make in 1861-'2 numerous experiments on the penetrability of iron plates; in the course of these he came to the conclusion that shot fired at moderate distances, from muzzle-loading, smooth-bored cannon of large calibre, possess greater power of penetrating and crushing iron plates than the projectiles of the breech-loading rifled ordnance. This result has excited much comment from eminent artillery officers in England and elsewhere. Since 1858 Sir William Armstrong has been engineer of the war department, and superintendent of the manufacture of cannon at the government foundery at Woolwich, and also manufactures a large number at his own works at Elswick.