Jan Ingenhousz

Jan Ingenhousz was born on December 8, 1730 in Breda, Netherlands. His mother died when he was young, but not much else is known about his parents, but they did have enough resources to provide Ingenhousz with a good education, including the Latin School in Breda, which he finished at sixteen and went on to study medicine at the University of Leuven, where he earned his medical doctorate in 1753. After finishing his doctorate he spent two more years attending lectures at the University of Leiden and returned to Breda to open a practice.

In addition to his practice Ingenhousz studied physics in his own laboratory, with his first successful publication at age 28. Because he was a Catholic there was no possibility of him getting a university position in the Netherlands and he remained there until his father died in 1764. Intending to travel Europe and study he started in England where he learned about smallpox vaccination. He became a master inocculator and successfully combated an epidemic in Hertfordshire. Upon the recommendation of John Pringle, a family friend, Ingenhousz traveled to Vienna where he inoculated the Empress Mary Theresa and her family. As a reward for his services Ingenhousz was appointed court physician.

In 1779 Ingenhousz returned to England and began research on photosynthesis. Photosynthesis is the process by which plants take up carbon dioxide out of the air and use it to make sugar. The process requires sunlight and produces oxygen gas. Ingenhousz experimented by placing plants under water and exposing them to sunlight. He noticed that they produce gas bubbles on the underside of their leaves. He collected this gas and identified it as oxygen, which Joseph Priestly had described only a few years earlier. In addition to the discovery of photosynthesis Ingenhousz is also the discovery of brownian motion from his observation to coal dust on the surface of alcohol. For his discoveries Ingenhousz was made a member of the Royal Society that same year, 1779.

Ingenhousz died on September 7, 1799 in Claine, England, where he is buried.


References:

Harvey, R.B. and Harvey, Helen M. Whittier; "Brief Paper on Jan Ingenhousz"; Plant Physiology (1930)5:282-287

McCarthy, Eugene M.; "Jan Ingenhousz"; Macroevolution.net

Jan Ingenhousz Wikipedia Entry