Johan D. Buttner may have received some training in medicine and related fields. He arrived at the Cape early in 1712 as a soldier, but became assistant at the hospital in 1715. After being examined and found competent by the chief surgeon, A. van den Oever, he was promoted to third physician in 1716, and junior surgeon the next year. In October 1717 he obtained a post as chief surgeon on the ship Sanderhoef, and visited the East during the next five years. When his contract expired he settled as a civilian doctor in Cape Town in 1723, where he died seven years later.
Buttner kept a journal during the years 1711-1712 and 1717-1721. Although the original is lost, extracts from it made by N.J. von Dessin* have survived. It contains good descriptions of the countries and peoples of the East, but little information relating to the Cape. He also wrote a "Korte beschrijving van terra de Natal" (Brief description of the territory of Natal), but owing to a lack of reliable information about the territory at the time this too is not of much interest. His most important work is a manuscript written probably in 1716 and titled Waare Relation und Beschrijbung von Cabo de Goede Hoop... (True account and description of the Cape of Good Hope). Though tedious, its description of the way of life and thought, medicines, language, and hunting techniques of the Khoi is of interest. It also includes descriptions of the geography of the Cape, and its birds and land animals.