induction coil
Date: late 19th-mid 20th Century
Inventory Number: 0342
Classification: Induction Coil
Subject:
User: Theodore William Richards (1868 - 1928)
User: Department of Chemistry, Harvard University (founded 1791)
Maker: P.K. / M
Cultural Region:
City of Use:
Dimensions:
15.6 × 24.9 × 15 cm (6 1/8 × 9 13/16 × 5 7/8 in.)
Description:
Induction coil with shiny black endpieces, on wood base with horizontal hammer. A short heavy coil moulded wood end caps. The card indicates that it was wound sectionally, and then covered with thin hard rubber wrapper. The high tension ends are mounted over the coil. The circuit breaker is a horizontal hammer. There is a reversing switch, and the base conceals the condenser. The coil may be wound in sections.
From instrument's card: "A short heavy coil with moulded wood end caps. Probably wound sectionally, covered with thin hard rubber wrapper, high terminals mounted over coil (not ends), regulation horizontal circuit breaker, lever reversing switch on rectangular moulded wood box base containing condenser."
From instrument's card: "A short heavy coil with moulded wood end caps. Probably wound sectionally, covered with thin hard rubber wrapper, high terminals mounted over coil (not ends), regulation horizontal circuit breaker, lever reversing switch on rectangular moulded wood box base containing condenser."
Signedside of base marked: P.K./M.
Inscribedbased numbered: 2686; marked on base: CARNEGIE / G.C.E 784 / SPARK / COIL
FunctionFor experimentation and demonstration of the high voltages induced in a secondary winding when the current in the primary windings is abruptly disrupted. The spark gap for this instrument was about 1/2 inch to 3/4 inch.
From #0343's file card: "The uses of an induction coil are very numerous. Some of these may be classified: Experimental - production of sparks - magnetic deflection - colors from metals of spark points - perforation of solids as plate glass. Shocks - entertainment - medical. Discharges in vacuum - luminous discharge - deflection and rotation - Geissler tube in vacuum tubes - phosphoresce and florescence of materials - stratification - spectra of gases. High Vacuum effects and X-Rays (but not till 1895)."
From #0343's file card: "The uses of an induction coil are very numerous. Some of these may be classified: Experimental - production of sparks - magnetic deflection - colors from metals of spark points - perforation of solids as plate glass. Shocks - entertainment - medical. Discharges in vacuum - luminous discharge - deflection and rotation - Geissler tube in vacuum tubes - phosphoresce and florescence of materials - stratification - spectra of gases. High Vacuum effects and X-Rays (but not till 1895)."
Historical AttributesInscriptions indicate that it was used by Professor Theodore William Richards (see card).
ProvenanceDepartment of Chemistry, Harvard University.