decade resistance box
Date: 1940
Inventory Number: 1997-1-1207
Classification: Resistance Box
Subject:
Maker: Leeds & Northrup Company (1903 - 1995)
User: Department of Geology and Geography, Harvard University (1890 - 1961)
Cultural Region:
Place of Origin:
Dimensions:
11 × 22.3 × 10.8 cm (4 5/16 × 8 3/4 × 4 1/4 in.)
Material:
Description:
Rectangular decade resistance box, consisting of three dials (of 1, 10, & 100 Ohms) and two terminals, or binding posts, assembled on a polished hard rubber top plate, which is mounted on a mahogany case. Each dial is numbered with two sets of 0-9, so that they can be set to any value without having to turn dial more than 90 degrees.
On market as early as 1927 to at least 1945 (see catalogs in primary sources references). In 1927 it was priced at $33.00; in 1945 it was priced at $28.00.
On market as early as 1927 to at least 1945 (see catalogs in primary sources references). In 1927 it was priced at $33.00; in 1945 it was priced at $28.00.
Signedon top panel: LEEDS & NORTHRUP CO. / PHILADELPHIA / 256290 / MADE IN U.S.A.
mounted plaque: PATENTED / LEEDS & NORTHRUP CO. / PHILADELPHIA / SER. NO. / MADE IN U.S.A.
mounted plaque: PATENTED / LEEDS & NORTHRUP CO. / PHILADELPHIA / SER. NO. / MADE IN U.S.A.
FunctionSuch an instrument is used to measure the resistance of electric conductors. For a short general description and other images, go to the following website.
This one is more recent but works on the same principle. The decade name comes from the fact that the resistance is measured in single units divided in four dials, each a multiple of 10, from 1 to 9999 Ohms.
This one is more recent but works on the same principle. The decade name comes from the fact that the resistance is measured in single units divided in four dials, each a multiple of 10, from 1 to 9999 Ohms.
Primary SourcesLeeds & Northrup, Electrical Resistance Measurements Catalog 40, 1927 [picture on p.10 matches instrument exactly]
Leeds & Northrup, D-C Resistance Measurements Catalog E-53, p. 26.
Leeds & Northrup, D-C Resistance Measurements Catalog E-53, p. 26.
ProvenanceFrom the Department of Geology and Geography, Hoffman Laboratory, Harvard University, 1984.