Christopher Polhem

Other fields

Polhem was not only active within the field of mechanics, he actively wrote essays concerning medicine, social criticism, astronomy, geology, and economics.

Polhem married Maria Hoffman on 28 December 1691. Together they had eight children between 1692 and 1705.

In 1716, he was ennobled by King Charles XII of Sweden in gratitude of his services to the nation by the king and changed his surname from Polhammar to Polheim, which he later shortened to Polhem.

He and his son Gabriel Polhem (1700–1772) were both elected members of the Royal Swedish Academy of Sciences in 1739, the same year the academy was founded.

Polhem died of natural causes in 1751 in Stockholm, at the age of 90.

Industrial

According to Polhem's autobiography, the event that marked the beginning of his career was the successful repair of the unfinished medieval (16th century) astronomical clock designed by Petrus Astronomus at Uppsala Cathedral, which had remained unfinished and broken for more than a century.

In 1690 Polhem was appointed to improve upon the current mining operations of Sweden. His contribution was a construction for lifting and transporting ore from mines, a process that was rather risky and inefficient at the time. The construction consisted of a track system for lifting the ore, as opposed to wires; the construction was powered entirely by a water wheel. Human labor needed was limited to loading the containers. Being new and revolutionary, word of Polhem's work reached King Charles XI of Sweden who was so impressed with the work that he assigned him to improve Sweden's main mining operation; the Falun Mine in Dalarna.

Funded by the Swedish mining authority, Polhem traveled throughout Europe, studying mechanical development. He returned to Sweden in 1697 to establish laboratorium mechanicum in Stockholm, a facility for the training of engineers, as well as a laboratory for testing and exhibiting his designs. It has since become the prestigious KTH Royal Institute of Technology, whose history began with Charles XI and his praise for Polhem for his mining efforts.

His greatest achievement was an automated factory powered entirely by water, Stjärnsund manufactory. The manufactory was financed by Gabriel Stierncrona. Built in 1699 in Stjärnsund, the factory produced a number of products including manufacture of knives, locks and clocks. Development of the factory was derived from the idea that Sweden should export fewer raw materials and instead process them within their own borders.

The factory met great resistance among workers who feared they would be replaced by machinery. Eventually most of the factory was destroyed in a fire in 1734, leaving only the part of the factory that produced clocks. The factory continued producing clocks, known for their high quality and low price. Although the popularity of the clocks diminished during the beginning of the 19th century, clock-making continues to this day at Stjärnsund, still producing around twenty clocks of the Polhem design per year.

Another product from the factory was the "Polhem locks" (Swedish: Polhemslås), essentially the first design of the variation of padlocks common today. Clocks and padlocks were both produced with interchangeable parts and the locking parts of the padlocks were coded so that customers could order reserve keys.

Economically, the factory was unfeasible, but the king at the time, Charles XII, was supportive and gave Polhem freedom from taxes to encourage his efforts. The factory of Stjärnsund was visited by one of his contemporaries, Carl Linnaeus, who wrote about the factory in his diaries as "Nothing is more optimistic than Stjärnsund" (Swedish: Intet är spekulativare än Stjärnsund).

Polhem also contributed to the construction of Göta Canal, a canal connecting the east and west coasts of Sweden. Together with Charles XII of Sweden, he planned the construction of parts of the canal, particularly the canal locks in the 18th century; it was not to be finished until 1832, long after his death.

Other major contributions made by Polhem were the constructions of dry docks, dams, and canal locks, which he designed together with his assistant and friend, Emanuel Swedenborg.