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
Six's thermometer lower (for minimum) than already recorded, in which case the relevant marker is pushed further. The markers thus record the furthest point reached by the mercury in each arm of the tube, and thereby the highest and lowest temperatures since the last reset. Typically the thermometer is reset every 24 hours to measure the diurnal temperature variation, the positions of the ends of the markers nearest to the mercury are examined. Their positions on the maximum and minimum scales show the highest and lowest temperatures encountered since the last reset. In a variation of design, some models have unsprung markers