Faraday's Ring or Hysteresis Coil


Here, a circular coil and three pairs of binding posts are mounted on a wooden base marked “WOOD / O.D. 100 / I.D. 71” while a metal bar is marked “WM GAERTNER & CO. / CHICAGO.” L. E. Knott called this small instrument a Faraday’s Ring and Demonstration Transformer, describing it as a simple apparatus “designed for study of the principles and laws involved in self and secondary induction.” The Chicago Apparatus Co. called it a “Hysteresis Coil. Designed to meet the requirements of Experiment No. 15 in Millikan and Mills, ‘Electricity, Sound and Light.’”

Ref: Robert Andrews Millikan and John Mills, A Short University Course in Electricity, Sound and Light (Boston, 1908), pp. 164-165.

Wm. Gaertner Co. Catalog (Chicago, 1929), p. 2.

L. E. Knott Apparatus Co., Catalogue of Physical Instruments (Boston, 1912), p. 466.

Chicago Apparatus Co., Physical Instruments, Apparatus, and Supplies (Chicago, ca. 1931), p. 239.

Maker: Gaertner Scientific Corporation

Location: Currently not on view

Place Made: United States: Illinois, Chicago

See more items in: Medicine and Science: Physical Sciences


Exhibition Location:

Credit Line: Richard J. Zitto

Data Source: National Museum of American History

Id Number: 2010.0235.44Catalog Number: 2010.0235.44Accession Number: 2010.0235

Object Name: Faraday’s ring or hysteresis coil

Physical Description: wood; metal (overall material)Measurements: overall: 1 3/4 in x 7 1/2 in; 4.445 cm x 19.05 cm

Guid: http://n2t.net/ark:/65665/ng49ca746ad-7157-704b-e053-15f76fa0b4fa

Record Id: nmah_1409626

Our collection database is a work in progress. We may update this record based on further research and review. Learn more about our approach to sharing our collection online.

If you would like to know how you can use content on this page, see the Smithsonian's Terms of Use. If you need to request an image for publication or other use, please visit Rights and Reproductions.