Faraday Ice Pail
   "Let A in the diagram represent an insulated pewter ice-pail, ...connected by a wire to a delicate gold-leaf electrometer E, and let C be a round brass ball insulated by a dry thread of white silk, three or four feet in length, so as to remove the influence of the hand holding it from the ice-pail below. Let A be perfectly discharged, and then let C be charged at a distance by a machine or Leyden jar, and introduced into A.. If C be positive, E will also diverge positively; if C be taken away, E will collapse perfectly... As C enters the vessel A the divergence of E will increase until C is ... below the edge of the vessel, and will remain quite steady and unchanged for any greater depression. 
This shows that that that distance the inductive action of C is entirely exerted upon the interior of A, ... If C is made to touch the bottom of A, all of its charge is communicated to A, ... and C, upon being withdrawn, ... is found to be perfectly discharged." (From a letter written by Michael Faraday to Richard Phillips, the editor of Phil. Mag. on February 4, 1843. The diagram is from L. Pearce Williams, Michael Faraday, A Biography (Simon and Schuster, New York, 1971), pg 374)

   And so introductory physics students have been studying the Faraday Ice Pail Experiment ever since, learning that in an electrically-conducting body, the charge resides on the surface. 

   Two almost identical ice pails at the top are from Colby College (left) and the University of Vermont (right). At the left below is an ice pail from Allegheny College, and the one at the right is in the Smithsonian Institution collection.
   The ice pail at the left is in regular use in physics lecture demonstrations at the University of Texas at Austin. The 1888 Queen catalogue lists it for $8.00, including a proof plane. This example dates from the early part of the twentieth century.

   Variations on the ice pail demonstration arrived soon after Faraday's letter. In 1855, George Francis's book, Electrical Experiments discussed the Electric Well demonstration: "Place upon an electric stood, a metal quart pot, mug, or some other conducting body, nearly of the same form and dimension, then tie a short cork ball electroscope, that is two cork balls suspended upon a linen thread, to a silken cord. Electrify the mug, and hold the electroscope within it, when it will not be at all affected."
 
 
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