Daniel Gabriel Fahrenheit research suggests that the Fahrenheit family originated in Hildesheim. Daniel's grandfather moved from Kneiphof in Königsberg (present-day Kaliningrad) to Danzig and settled there as a merchant in 1650. His son, Daniel Fahrenheit (the father of the subject of this article), married Concordia Schumann, daughter of a well-known Danzig business family. Daniel was the eldest of the five Fahrenheit children (two sons, three daughters) who survived childhood. His sister, Virginia Elizabeth Fahrenheit, married Benjamin Ephraim Krueger of an aristocratic family from Danzig. Daniel Gabriel began training as a merchant in Amsterdam after his parents died on 14 August 1701 from eating
Medical thermometer the "Académie des sciences, belles-lettres et arts de Lyon", developed a similar scale in which "0" represented the freezing point of water and "100" represented boiling. On 19 May 1743 he published the design of a mercury thermometer, the "Thermometer of Lyon" built by the craftsman Pierre Casati that used this scale. The medical thermometer was used by Dutch chemist and physician Hermann Boerhaave (1668–1738), as well as his notable students Gerard van Swieten (1700–72) and Anton de Haen (1704–76). It was also utilized around the same time by Scottish physician George Martine (1700–1741). De Haen made particular strides in