Accession No
5348
Brief Description
mercury-in-glass thermometer, E-Mil brand, by H. J. Elliot Ltd., 20th Century
Origin
Wales; Nr. Pontypridd; Treforest Trading Estate
Maker
H. J. Elliot Ltd.
Class
thermometry
Earliest Date
1900
Latest Date
1998
Inscription Date
Material
glass; metal (mercury, other); paper (card); plastic
Dimensions
length of thermometer 600mm; diameter 18mm; length of case 625mm; diameter 32mm
Special Collection
Provenance
Donated by Barry Fuller and transferred from the Department of Zoology, University of Cambridge, Cambridge, England and 06/11/1998.
Inscription
Description Notes
Very long bulb mercury in glass thermometer in its original card carton given by Zoology Department, University of Cambridge. 20th Century. Maker E-MIL H.J. Elliot Ltd.
In glass envelope with metal cap and suspension loop. White plastic insert with black ink etched celcius scale. Scale is 0 - 1˚. Division of 0.02 degrees. On the back of the plastic insert is etched ‘E-MIL MADE IN ENGLAND’ and ‘Dw33257’. At top of thermometer above the primary scale is a secondary scale which registers 0-100˚ in
2 ˚ divisions. At the top of the glass jecket is a metal cap with hole for hanging the thermometer from.
The cartoon is rolled card (like a toilet roll) covered in black paper/card. On the outside centre position is the makers label with faded ink detailing contents.
Condition of thermometer good, of cartoon good - fair
References
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:45684
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