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Faraday apparatus accessories
Faraday apparatus accessories

Faraday apparatus accessories

Date1860-1880
Inventory Number1997-1-0255b
ClassificationElectromagnetic Apparatus
Subject
    Attributed to Heinrich Daniel Ruhmkorff 1803 - 1877
    Cultural Region
      Dimensions38.5 x 60 x 25 cm (15 3/16 x 23 5/8 x 9 13/16 in.)
      Material
        Bibliography
        DescriptionThis magnetic solenoid consists of four gilded steel feet screwed sideways support the instrument. It consists mainly of two large perforated iron cylinders on which coils have been wound around. Their axes are in the same horizontal line. When electricity passes through the coils (from the connectors at each end of the instrument), it creates a powerful magnetic field inside the longitudinal cavities. The two cylinders can slide away from each other, a scale indicating in millimeters the empty space between them. Two large wingnuts underneath the base fixed the cylinders in place. Accessories (b) are stored in a separate box
        Signedunsigned
        FunctionWas used to measure the Verdet constant of materials. It is an optical constant. To measure it, a beam of light was sent in the horizontal axis of the two cylinders towards a transparent material, passing within the strong magnetic field generated by the apparatus. Simply said, Emile Verdet discovered that the rotation of the plane of polarization is proportional to the strength of the magnetic force.

        A video demonstration of a Ruhmkorff electromagnet by the Fondazione Scienza e Tecnica in Florence is available on Youtube here.
        Faraday apparatus
        Heinrich Daniel Ruhmkorff
        Date: 1860-1880
        Accessories: instrument parts of various shapes and sizes (b)
        Object number: 1997-1-0255a
        induction coil
        Heinrich Daniel Ruhmkorff
        Date: circa 1859
        Object number: 0343
        classroom demonstration galvanometer
        Heinrich Daniel Ruhmkorff
        Date: 1850-1875
        Object number: 0446
        induction coil
        Heinrich Daniel Ruhmkorff
        Date: circa 1859
        Object number: 0502
        astatic galvanometer with moving magnet
        Heinrich Daniel Ruhmkorff
        Date: circa 1859
        Object number: 0193a,b
        Hibbert's balance
        W.G. Pye & Company, Ltd.
        Date: circa 1920
        Accessories: 5 accessory parts: 2 magnetic rods with spherical ends; one brass notch; needle with tip inserted into cork;
        Object number: 1997-1-0662
        Hibbert's magnetic balance
        Walter Hibbert
        Date: early 20th Century
        Accessories: 7 accessory parts: 2 magnetic rods with spherical ends; 4 brass notches; needle with tip inserted into cork;
        Object number: 1997-1-0661
        optical bench with Millikan oil drop experiment set-up
        Heinrich Daniel Ruhmkorff
        Date: 1860-1875
        Object number: 1996-1-0531
        electric spark discharger
        Heinrich Daniel Ruhmkorff
        Date: circa 1860
        Object number: DW0013
        device to measure electrical resistance of solutions
        Heinrich Daniel Ruhmkorff
        Date: 1850-1870
        Object number: DW0852
        Melloni optical bench with accessories
        Heinrich Daniel Ruhmkorff
        Date: 1860-1875
        Object number: 2006-1-0013
        telegraph receiver
        Western Electric Company
        Date: circa 1904
        Object number: 1997-1-0562