induction coil
Date: circa 1870
Inventory Number: 0340
Classification: Induction Coil
Subject:
Maker: Adolphe Gaiffe (1832 - 1887)
User: Department of Physics, Harvard University (founded 1884)
Cultural Region:
Place of Origin:
City of Use:
Dimensions:
9.5 × 17 × 9 cm (3 3/4 × 6 11/16 × 3 9/16 in.)
Description:
Induction coil on wood base (black windings) with hammer-style contact breaker. A small simple winding coil. The high tension terminals are mounted on the two opposite end pieces (wood). The circuit breaker is a horizontal vibrating hammer. The wood base conceals the capacitor. No. 38370.
From instrument card: "A small bobbin probably of simple winding, round wooden ends on which are located the 'high' terminals. A standard horizontal circuit-breaker shields reverse switch, all on rectangular wood box base containing condenser. Very likely a cheap production model. The conductor is made of sheets of tin-foil and paper from old ledger."
From instrument card: "A small bobbin probably of simple winding, round wooden ends on which are located the 'high' terminals. A standard horizontal circuit-breaker shields reverse switch, all on rectangular wood box base containing condenser. Very likely a cheap production model. The conductor is made of sheets of tin-foil and paper from old ledger."
SignedWith punch mark on base, superimposed: AG [mark of Adolphe Gaffe]
Inscribednumber on base: 38370
FunctionFor experimentation and demonstration of the high voltages induced in a secondary winding when the current in the primary windings is abruptly disrupted.
This one produces a 1/4 inch spark.
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)."
This one produces a 1/4 inch spark.
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)."
ProvenancePhysics Department, Harvard University.