Accession No
1889
Brief Description
mercury-in-glass Reaumur thermometer, French, 1780 (c)
Origin
France
Maker
Class
thermometry
Earliest Date
1780
Latest Date
1780
Inscription Date
Material
metal (mercury); glass; wood
Dimensions
box length 323mm; breadth 42mm; thickness 16mm
Special Collection
Provenance
Purchased from Harriet Wynter, 352 Kings Road, Chelsea, London, SW3 5UU, in 03/1974.
Inscription
‘Thermometre
Selon Reaumur’ (marked across the top of the open faces)
Description Notes
Long-bulb mercury in glass Réaumur thermometer set in a hinged wooden frame; inner faces painted cream; in the left hand face is the thermometer with ink calibrations -15oR-0oR to [72]oR by 5o subdivided to 1o. On the right hand face of the cover are certain temperatures indications 30oR ‘Chalhum’ [body heat], 25˚R ‘Bains’ [bath], 19˚R ‘Vers a Soye’ [silk worms], 15˚R ‘Serres’ [hothouses], 9.5˚R ‘Temperee’ [temperate], 6oR ‘Orangerie’ [orangery], 0oR ‘Glace’, -4oR ‘Noirres gelees’ [black ice] -10.5oR ‘Paris 1740’, -15oR ‘1776’. [These may be the two coldest temperatures registered in Paris]
Hook fastening (hook missing).
Condition: fair.
References
Allison Ksiazkiewicz; 'Early thermometers and temperature scales'; Explore Whipple Collections online article; Whipple Museum of the History of Science; University of Cambridge: https://www.whipplemuseum.cam.ac.uk/explore-whipple-collections/meteorology/early-thermometers-and-temperature-scales
Events
Description
A thermometer is an instrument that measures how hot or cold something is, in other words, its temperature. Most familiar is the "Mercury-in-glass" thermometer, but there are many other kinds.
Many materials expand as they get hotter and contract as they get colder . This expansion and contraction can be used to measure the corresponding changes in temperature. Thus the first useful thermometers were made from a glass bulb full of mercury to which was attached a narrow glass tube. As the bulb is heated a fine thread of mercury expands up the narrow tube. Thermometers, requiring great skill in glass working, were first made by Daniel Fahrenheit of Amsterdam in 1717.
To measure temperature precisely, a numerical scale of "degrees" is needed. To provide this scale two fixed points are chosen, such as melting ice and boiling water. Convenient temperatures are then given to these two fixed points: today melting ice is given a temperature of 0 degrees and boiling water 100 degrees. This is the Celsius or Centigrade scale (although it is quite arbitrary). Fahrenheit himself originally chose the coldest temperature that he could produce (a freezing mixture of ammonium chloride and snow) as 0 degrees and body temperature as 96 degrees. This resulted in the Fahrenheit scale in which the freezing point of water is 32° F and the boiling point of water is 212° F.
01/03/2001
Created by: Chris Lewis on 01/03/2001
FM:42210
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