John Ericsson was born on July 31, 1803 in Langbanshyttan, Sweden. His father, John was the supervisor of a local mine and land speculator. When several of his investments turned sour, he was forced to move his family to Forsvik in 1810. There, he became the director of demolitions for the excavation of the Gota Canal.
John and his brother Nils were made cadet mechanics in the Swedish Royal Navy and helped with the Canal project as well. By the age of fourteen, John was working as a surveyor and had an assistant that carried a stool for him to stand on while surveying. He continued to work on the Canal project for the next three years.
In 1820, at the age of seventeen, John joined the Swedish Army and was assigned to the Jemtia Field Ranger Regiment with the rank of Second Lieutenant. Soon after joining, he was promoted to the rank of Lieutenant and was assigned to do surveying in northern Sweden. During his free time, he started working on inventions and developed an engine that used fumes from fire as a propellant.
In 1826, John quit the Army in order to pursue his engineering interests. He moved to England, where he built a prototype of his engine that ran off of birch wood. However, since England was mostly powered by coal at the time, the engine was not a commercial success.
After that project, he developed several steam engines. His major achievements involved increasing the heat output by using fans to increase the oxygen supply to the fire. He entered one such engine, dubbed "novelty", into a competition funded by the Liverpool and Manchester Railway. His engine performed fairly well and ran the fastest, but it was unable to finish due to problems with the boiler.
In 1829, he married a woman named Amelia Byam. He continued to work on steam engines, despite losing tremendous amounts of money in the process. Eventually, he decided to move onto improving ship designs. He proposed building ships with dual screw propellers that could move in different directions. The British Navy did not like the design, but he was able to get a contract with an American named Robert Stockton.
Stockton contracted John to design a steam ship and they returned to New York City in 1839 to work on this project. They worked together to secure funds for the project and were able to get a grant from President Tyler. Ericsson set to work, producing a 700 ton sloop that became known as the USS Princeton. The project took three years to complete, but the end product was the most advanced naval weapon of the time.
Along with dual propellers, the ship featured several other innovations. The bow of the ship featured a twelve-inch muzzle loading gun on a revolving base. He designed the gun himself and made it using a "hoop construction" that tensioned the breech for additional strength.
Despite all of Ericsson's hard work on the project, his relationship with Stockton turned sour. Stockton tried to take credit for the ship's design and created a second, inferior gun on the rear of the ship. The ship set sail in 1843 and won a speed contest versus the SS Great Western to become the fastest steamer on the water.
Later, a number of important officials were brought on board the ship for a demonstartion of its firing capabilities. During a test fire of the second gun, its barrel exploded and the resulting shrapnel killed the Secretary of State, Secretary of the Navy, and six other people. Stockton placed full blame on Ericsson for the accident and succeeded in blocking the Navy from paying him.
In 1852, Ericsson developed what he called a "hot air engine". Rather than steam, the engine used hot air as a propellant, but it failed to become a commercial success. For his design, he was awarded the Rumford Prize of 1862. In 1854, he visited Napoleon the 3rd, Emperor of France, and gave him drawings of proposed iron-clad warships. Napoleon failed to recognize the importance of the idea and refused to fund the construction of any prototypes.
In 1861, after the outbreak of the Civil War in the United States, the Confederacy started building an ironclad battleship. The United States government decided to counter this by hiring Ericsson to build an ironclad for the US Navy. He designed a schematic and was given the funding to construct it, producing a working model on March 6, 1862. It was dubbed the USS Monitor and proved its worth during a battle with the CSS Virginia on March 9, 1862. The Monitor successfully defended the Union's fleet from the Confederate Navy and the United States immediately began constructing more.
After designing the Monitor, Ericsson began working on designing torpedoes. He also designed a solar engine that used sunlight to heat air that was used as a propellant. His late career declined until he died on March 8, 1889 from natural causes.