Images(5)

portable galvanometer with telescope

Datecirca 1910

Inventory Number0282

ClassificationGalvanometer

Subject

Maker Leeds & Northrup Company 1903 - 1995

User Harvard Engineering School 1918 - 1951

Cultural Region

Place of Origin

Place of Use

Dimensions11.3 × 10.8 × 23.3 cm (4 7/16 × 4 1/4 × 9 3/16 in.)

Material

Accessoriescarrying case; spare self-contained mirror and moving coil

DescriptionA portable galvanometer with telescope and scale. The galvanometer consists of a self-contained mirror and moving coil on a delicate wire suspension with two binding posts at base. Paper scale is graduated from 0-40. Scale and telescope are detachable or collapsible to fit in oak carrying case with leather strap (broken). There is a yellow triangle painted on the galvanometer.

For a full description of this particular galvanometer, read the patent number 843,414 here.

Signedon galvanometer: THE LEEDS & NORTHRUP CO. / PHILADELPHIA on scale: THE LEEDS & NORTHRUP CO.

Inscribedon case (serial number): 29181 inside box lid on steel plate: PATENTED / FEB. 5TH. 1907

FunctionA reflecting galvanometer with a moving magnet is a sensitive instrument that measures small current displacements. When an electric current passes through the wire coil, it induces a magnetic field that causes the magnet and the mirror attached to it to rotate in proportion to the current deflections, and the current deflections can be detected using a scale.

ProvenanceFrom Engineering School, Harvard University.