Signedunsigned
Inscribedengraved on scale: Max. Min. / Centigrades
FunctionThermometer. The metal strip is made of two different metals, which expand at different rates with a change in temperature. Hence the coil winds or unwinds a little, moving the pointer along. It also registers minimum and maximum temperature.
Historical AttributesThis maximum-minimum thermometer is in the style of one devised by Hermann & Pfister of Berne.
Primary SourcesHermann and Pfister, Schweiz. meteorol. Beobb. für 1867, 15-18.
ProvenanceTag "from Jeff Prep 3/12/67". From the Jefferson Physical Laboratory, Physics Department, Harvard.
Related WorksW. E. Knowles Middleton, A History of the Thermometer and Its Uses in Meteorology (Baltimore: Johns Hopkins Press, 1966), 172-173.