double thermopile
Date: 1880-1910
Inventory Number: 1998-1-1431
Classification: Thermopile
Subject:
heat,
Maker: French
User: Department of Physics, Harvard University (founded 1884)
Cultural Region:
Dimensions:
34 × 19.5 × 9.8 cm (13 3/8 × 7 11/16 × 3 7/8 in.)
Description:
A lead-weighted telescoping stand supports a small cylindrical housing opened at both ends. Each end has a radiation cone (tarnished inside) designed to focus heat radiation on the thermocouples. The latter are found at the back of each cone, linked to binding posts. The housing can be tilted vertically.
A small blue dot has been painted on the housing, meaning it was originally owned by the physics department at Harvard. There is also a number stamped on the top of the base: "9-209".
A small blue dot has been painted on the housing, meaning it was originally owned by the physics department at Harvard. There is also a number stamped on the top of the base: "9-209".
In Collection(s)
Signedunsigned
FunctionThis instrument is used to measure the difference of temperature of radiating sources, light included. The radiation entering from one or both ends of the instrument heats up the thermocouples, which produce a small electrical current. The latter is transmitted to a galvanometer that measures it. From this quantitative number, the amount of radiation can be derived.
For a general discussion of such an instrument, go to the following website.
For a general discussion of such an instrument, go to the following website.
ProvenanceFrom the Department of Physics, Harvard University.