decade resistance box
Date: circa 1920
Inventory Number: 1997-1-1187
Classification: Resistance Box
Subject:
Maker: Leeds & Northrup Company (1903 - 1995)
User: Department of Physics, Harvard University (founded 1884)
Cultural Region:
Place of Origin:
City of Use:
Dimensions:
10.5 × 22 × 10.5 cm (4 1/8 × 8 11/16 × 4 1/8 in.)
Material:
Description:
Decade resistance box consisting of three black, rounded dial switches valued at 1, 10, and 100 ohms, each with ten steps. There are also two small metal binding posts above the dials. These elements are mounted on a hard rubber panel over a rectangular mahogany base. The internal resistance consists of five coils for each dial switch, mounted in the wooden case.
The blue triangle on the instrument indicates that it was once used in the Harvard University Physics 3 laboratory course.
The blue triangle on the instrument indicates that it was once used in the Harvard University Physics 3 laboratory course.
Signedon top panel: LEEDS & NORTHRUP CO. / PHILADELPHIA / 26010
Inscribedsmall plaque mounted on wooden case: PATENTED / JULY 28, 1914
dials marked: UNITS
dials marked: UNITS
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.
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.
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.
ProvenanceFrom the Department of Physics, Jefferson Laboratory, Harvard University.