Accession No

1271

Brief Description

mercury-in-glass thermometer, measurements according to the Réaumur scale and metric system, by Robert-Aglaé Cauchoix, French, 1830

Origin

France; Paris; quai Voltaire No.17

Maker

Cauchoix, Robert-Aglaé

Class

laboratory apparatus; thermometry

Earliest Date

1830

Latest Date

1830

Inscription Date

Material

metal (mercury); glass; paper; cloth (velvet; silk); wood; hide (leather?)

Dimensions

box length 212mm; breadth 27mm; thickness 22mm

Special Collection

Robert Whipple collection

Provenance

Donated by Robert S. Whipple.

Inscription

‘Thermometre Selon Reamur et la Systeme Decimal. Par Cauchoix, quai Voltaire No17 a Paris’ (signed on scale)

Description Notes

Long-bulb mercury in glass Réaumur and Celsius thermometer, with calibrations on paper set in a separate parallel tube. Running parallel to the thermometer stem and fixed by a glass loop above the bulb and a glass U-bend at the head a 10 mm od tube containing the handwritten paper scale calibrated to the left (-24)oC-0-(107)oC by 5 to 1o; and to the right (-19)oR-0-(86)oR by 5 to 1o with on the right the indications: (80)’Eaubte’’ (25) ‘Baind’, (9.5) ‘Tempere’, (0) ‘Glace’ (-10.5) ‘1740’.
Fitted box, lined in velvet and silk.

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:42209