galvanometer with moving coil
Date1910-1930
Inventory Number0189a,b
ClassificationGalvanometer
Subject
Maker
L. E. Knott Apparatus Company
1896 - early 1930s
User
Department of Chemistry, Harvard University
founded 1791
Cultural Region
Place of Origin
Place of Use
Dimensions38 x 25.5 x 24.6 cm (14 15/16 x 10 1/16 x 9 11/16 in.)
blue board box: 39.1 × 26.7 × 30.2 cm (15 3/8 × 10 1/2 × 11 7/8 in.)
blue board box: 39.1 × 26.7 × 30.2 cm (15 3/8 × 10 1/2 × 11 7/8 in.)
Material
Accessoriesbell jar
DescriptionGalvanometer (0189a) with moving coil and mirror on fine wire suspension which can be rotated mechanically by a rod, chain, and knurled wheel (beneath the base). Several layers of circular magnets with poles which extend to the center encased coil. Enlarged circular scale surrounds outside of magnets and coil. Scale marked every 5 units and labeled every 10 units from 0-90-0-90-0. Meter is attached to round wooden base with three leveling screws and one binding post and is covered with a bell jar (0189b, not pictured). Bell jar badly cracked and patched with masking tape.
Signedon scale: KNOTT - BOSTON / -No 93-175
FunctionThis galvanometer was used for demonstrations in a chemistry classroom. The galvanometer measures small current displacements. When an electric current passes through a wire coil, it induces a magnetic field that causes the coil to rotate in proportion to the current deflections, twisting a suspended magnet. The current deflections can be detected using the attached scale.
ProvenanceFrom the Department of Chemistry, Harvard University, 11/21/1956.
L. E. Knott Apparatus Company
Date: circa 1910
Object number: 0451
Harvard Cyclotron Laboratory
Date: 1947-2002
Object number: 2003-1-0291
Panelvision Corporation
Date: 1984
Accessories: single-board display controller
cable for display (1997-1-0686c)
shipping ticket/ hand carry pass dated June 11, 1997 (in instrument file)
letter to Dr. Richard V. Kollarits from William Andrewes dated June 16, 1997 regarding donation of MiniGraphic display and letter to William Andrewes from Dr. Richard V. Kollarits that accompanied the object upon donation on June 11, 1997 (in instrument file)
four sample color prints made with this display on micro-encapsulated photographic paper. 1. man in business suit, 2. woman crouching next to lawn ornament, 3. two clowns painting a third's face, 4. woman in winter hat and scarf (in instrument file)
copies of two articles by AT&T Bell Laboratories staff (Richard V. Kollarits, William, H. Ninke, David C. Gibbon) on color imaging and printing (in instrument file)
Panelvision pamphlet introducing the MiniGraphic multipurpose flat panel display, including instrument specifications, consumer prices, functioning and features (in instrument file)
1984 article by Panelvision employees (Peter Brody Fang-Chen Luo, Paul Malmberg) on active matrix technology (in instrument file)
Panelvision Corporation Fact Sheet, including details of company history and recent developments (in instrument file)
article about commercial debut of active matrix technology from Design Engineering newspaper, June 18, 1984 (in instrument file)
full circuit diagram and schematic for MiniGraphic Display Controller (in instrument file)
instruction manual and description of MiniGraphic Display Controller (two copies, in instrument file)
circuit diagrams and instruction manuals for the MiniGraphic Display (two booklets, in instrument file)
Object number: 1997-1-0686a
Charles-Louis Chevalier
Date: circa 1840
Accessories: 2 convertible objectives: 1, 2, 3 and 0,00,000; 2 oculars; simple magnifiers: 3 and 5, with support bracket; extension pillar; bull's eye stage condenser on jointed arm; forceps; 3 prepared slides; box of cover glasses; 1/100 mm stage micrometer; camera lucida; tall bell jar; padlock on chain; case with key; table of magnifications
Object number: 1079
Arnheiter
Date: 1830-1840
Accessories: magnets (2); wooden handle with hook; case
Object number: DW0899
Queen & Company
Date: circa 1910
Accessories: carrying case (may not be original to instrument)
Object number: 0267a,b
