John Ericsson

Ericsson's father supervised mine works in Värmland until speculation ruined him, and the family moved to Forsvik in 1810 so he could blast rock for the Göta Canal instead. The son surveyed alongside him from early childhood — so small that an assistant carried a footstool so he could reach the instruments — and passed a surveyor's examination in Stockholm at 18. He served as an army lieutenant, then crossed to England in 1826 to sell his mechanical ideas. His locomotive Novelty lost the Rainhill Trials to Stephenson's Rocket in 1829, a boiler fault undoing a machine contemporaries had called the faster of the two, and unpaid development bills eventually put him in debtors' prison.

The British Admiralty had already turned down his screw propeller once when Captain Robert Stockton hired him in 1841 to help design USS Princeton, the Navy's first screw-driven warship. Stockton then built his own oversized gun for it, the Peacemaker, without consulting Ericsson's specifications. It burst during a demonstration cruise on February 28, 1844, killing the secretaries of state and the navy along with six others — Ericsson's own gun on the same ship worked fine — and Stockton blamed him anyway, blocking his Navy pay for years. Eighteen years later the Navy needed him again: the ironclad Monitor went from keel to launch in about 100 days, met CSS Virginia off Hampton Roads on March 9, 1862, in the first fight between ironclads, and put a revolving gun turret on warships permanently.

He was not an easy man to work for or with. Colleagues called him arrogant and litigious, quick to claim sole credit and slow to forgive the Navy for the payment it never made him after the Princeton disaster. He married 19-year-old Amelia Byam, and the union failed almost immediately — the two lived apart for the rest of her life, with no recorded child between them. The one relationship that reached him was with the industrialist Cornelius DeLamater, who had financed the Monitor's engines — the two men used private nicknames for each other, dined together for decades, and when DeLamater died on February 2, 1889, days after Ericsson himself had taken to his bed, associates said he could not be consoled. Ericsson died five weeks later.

Congress and Sweden both wanted him kept, and settled for a corpse: after protests that the transport ship first offered was too small an honor, the Navy sent USS Baltimore across the Atlantic under a 21-gun salute, and about 100,000 people watched the funeral procession through Stockholm in 1890, a year after he died. He is buried near his birthplace at Filipstad. Monuments to him stand in four cities and a Sierra Nevada peak carries his name, but the invention that lasted was not the caloric engine he spent decades perfecting, largely forgotten now — it was the revolving turret, still standard on warships built more than a century and a half later.

John Ericsson's life against the full span of the corpus.

• Novelty locomotive invention
  Lost the Rainhill Trials to Stephenson's Rocket 1829
• Screw propeller invention
  Rejected by the British Admiralty, adopted by the U.S. Navy instead 1836
• USS Princeton invention
  The Navy's first screw-propelled warship, and the site of the Peacemaker disaster 1843
• Caloric engine invention
  An early hot-air engine, awarded the Rumford Prize in 1862 1852
• USS Monitor invention
  Keel to launch in about 100 days, with the first rotating gun turret 1862

• July 31, 1803 aged 0 Born in Långban, Sweden
• 1818 aged ~15 His father dies, ending the family's mining income
• March 27, 1822 aged 18 Passes a surveyor's examination in Stockholm at 18
• 1826 aged ~23 Emigrates to England to sell his mechanical designs
• 1829 aged ~26 The Novelty loses the Rainhill Trials to Stephenson's Rocket Boiler trouble, not speed, decided the contest.
• February 28, 1844 aged 40 Stockton's Peacemaker gun bursts aboard USS Princeton It killed the secretaries of state and the navy. Ericsson's own gun on the ship performed as designed.
• March 9, 1862 aged 58 USS Monitor fights CSS Virginia to a standstill at Hampton Roads
• February 2, 1889 aged 85 Cornelius DeLamater, his closest friend, dies
• March 8, 1889 aged 85 Dies in New York, 27 years to the day before the Monitor fight's anniversary

• Abraham Lincoln 1809–1865
  16th President who preserved the Union during the Civil War and issued the Emancipation Proclamation. built the ironclad for his navy
• Robert Fulton 1765–1815
  Engineer and inventor whose steamboat Clermont revolutionized American river transportation. predecessor in steam navigation
• David Farragut 1801–1870
  The U.S. Navy's first admiral, whose victories at New Orleans and Mobile Bay were decisive in the Civil War. supplied ironclads to his navy
• Ulysses S. Grant 1822–1885
  18th President and Union Army general whose leadership was decisive in winning the Civil War. the war his ironclad helped win