Thermometer made by Fahrenheit sells for over 67,000 pounds

The brass instrument is one of only three known examples of Fahrenheit's work in existence today.

It was thought to have been lost to history until it emerged for sale at Christies in London having been in private ownership for more than 40 years, the Daily Mail reported.

The 4.5 inches tall item got bidders hot under the collar when it went under the hammer, eventually going to an anonymous telephone buyer who paid 67,250 pounds for it.

Fahrenheit invented the mercury thermometer in 1714, but it is unknown exactly how many he made.

It divided the freezing and boiling points of water into 180 degrees.

The freezing point of water was 32 degrees fahrenheit and 212 degrees fahrenheit was the boiling point of water, set by Fahrenheit himself.

Zero degrees fahrenheit was based on the temperature of an equal mixture of water, ice, and salt. Fahrenheit based his scale on the temperature of the human body.

The Fahrenheit scale was the first widely used temperature scale.

The scale on the newly-discovered thermometer is marked from '0' to '132' degrees Fahrenheit and it is so small that the numbers had to be written on both sides of the mercury tube.

The device is signed 'Fahrenheit Amst', from the time the inventor worked in Amsterdam, where he made it.

This example has been in a private collection for over 40 years and it was unknown to scientific historians until now.

James Hyslop, from auctioneers Christie's, said in August when the auction was announced: "Until now, only two originals were thought to exist. And these are both in the Boerhaave Museum in the Netherlands. So to have this one emerge is very exciting."

"It is impossible to pinpoint exactly when it was made, but one in the museum is dated 1718, and this was probably made between 1715 and 1730," Hyslop said.