Jonathan Hornblower (1753-1815)
Jonathan Carter Hornblower (July 5, 1753 - February 23, 1815) was an English pioneer of steam power, the son of Jonathan Hornblower and brother of Jabez Carter Hornblower, two fellow pioneers.
He was born on 5 July 1753 at Chacewater, Cornwall, the sixth child and fourth son of Jonathan Hornblower (1717–1780), steam engine builder, and his wife, Ann Carter. Jabez Carter Hornblower (1744–1814) was his brother.
He was probably educated at Truro grammar school before being apprenticed to a plumber or brazier at Penryn, Cornwall, and lived at Trelever where he was baptized on 25 July 1773.
He was following his trade in 1779 at Penryn when he supplied some copper pipes for the engine at Poldory mine which his father was erecting for Boulton and Watt.
He married Rosamund (either Phillips or Mudge) who died in 1779, and then in 1786 Elizabeth Jordan, who died four years later, leaving two daughters.
He developed a compound engine in 1781 and patented the two stage engine but was prevented from pursuing his invention by litigation with James Watt over the separate condenser, an infringement of his intellectual property. He did install an engine at Radstock near Bath having cylinders 19in. and 24in. in diameter.
In other developments in steam technology, however, he was more successful and he died a rich man.
His foundry and works at Penryn flourished for he left a considerable estate, close to £10,000, when he died at Penryn on 23 February 1815.