The life of Dr Jan Ingen Housz (1730-99), private counsellor and personal physician to Emperor Joseph II of Austria.

A brief biography is presented of Dr Jan Ingen Housz, as written, originally in Dutch, by M J Godefroi, a mid-nineteenth-century Dutch physician who was a friend of a near descendant of Dr Ingen Housz. From being a general practitioner at Breda, his home town, he moved to England to learn smallpox inoculation, was sent to inoculate members of the Habsburg family at Vienna and dedicated his later life to scientific experimentation, notably revealing the fundamentals of photosynthesis.