“If it was the warmth of the sun, and not its light, that produced this operation, it would follow, that, by warming the water near the fire about as much as it would have been in the sun, this very air would be produced; but this is far from being the case” (Jan Ingenhousz). Jan Ingenhousz was born on December 8, 1730 in the city of Breda, Netherlands. Jan was a Dutch physician, chemist, and plant photosynthesis. In fact, he is known for his discovery of photosynthesis and the work of small pox vaccination. In his study of photosynthesis, Jan showed that light is significant to plant respiration and gas plants produce in light is called oxygen. At the age of 16, he began his study of medicine at a medical school, the oldest university in Belgium,…show more content… Then, he studied two years at University of Leiden where he attended the speeches by Pieter Van Musschenbroek, and became interest in electricity. In 1775, Ingenhousz began his practice as a physician. After his father’s death in 1764, he decided to travel to England to learn about the latest skill in small pox vaccination. In England, he became known by Benjamin Franklin, Henry Cavendish, and Joseph Priestley. Jan became the leading supporter of variolation. Variolation is an early method of small pox vaccination that involved in injecting patients with small pox virus taken from patients with a mild form of disease. During an outbreak of the disease in Hertfordshire in 1767, Ingenhousz used his method to vaccinate 700 people against small pox and for the family of King George III. A year after, austro Hungarian ruler, Maria Theresa, was scarred by smallpox and decided to have her entire family be vaccinated even though her doctors did not agree with her. Maria Theresa wrote to George for his advice for the best physician, and his recommendation was Jan Ingenhousz. Jan travelled to Austria, and vaccinated Theresa’s three youngest children. Also, he became Maria and her son, Joseph II, personal
