One of just three original examples of the Daniel Fahrenheit thermometer has sold for £67,250 ($107,802) at a Christie's auction in London.
Recently discovered in a private collection after residing there for 40 years, it is the only one of the three not in the Netherlands' Boerhaave Museum - a factor that helped increase its attraction to bidders.
Dutchman Fahrenheit invented the mercury thermometer in 1714. It is unknown how many he produced or when he began making the thermometers commercially, although one of the two in the Boerhaave is dated 1718.
Fahrenheit had previously made barometers with thermometers attached, and invented the alcohol thermometer years before the mercury example.
His mercury thermometers also led to the creation of the Fahrenheit scale in 1724, which is still in use in the US today.
James Hyslop, a scientific specialist at Christie's, said prior to the sale: "It is very exciting to be able to offer at auction such an incredibly important scientific instrument, and one which collectors would never have believed would come to market."
For science collectors we are currently offering an extremely rare example of Thomas Edison's stock ticker machine, one of his earliest inventions.
The thermometer shared top spot at the Travel, Science and Natural History auction on October 9 with a letter detailing the discovery of the bodies of Antarctic explorer Captain Scott and his colleagues, which sold for £67,250 ($107,802).
The sale also featured a rare second world war Enigma cipher machine, which sold for £58,850 ($94,337). The world record for one of the machines stands at £133,250 ($208,137), set by an example with its original box in 2011.