The letters of Faraday and Schoenbein, 1836-1862 : with notes, comments and references to contemporary letters / edited by Georg W.A. Kahlbaum and Francis V. Darbishire.

Date:
1899
Catalogue details

Licence: Public Domain Mark

Credit: The letters of Faraday and Schoenbein, 1836-1862 : with notes, comments and references to contemporary letters / edited by Georg W.A. Kahlbaum and Francis V. Darbishire. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

    46/404 (page 26)
    must be fulfilled.' In the first and second case the oxidized iron wire EF is to be replaced by a wire, whose end E is covered with peroxide of lead, every other thing remains the same as stated in my letter. As to the third fact, C P D is to be an iron wire having its end D associated with peroxide of lead; EF is to be a common iron wire. With respect to the fourth case, E instead of being oxidized must be covered with peroxide of lead. To obtain a result analogous to the fifth fact, the iron wire CPD its end D being associated with the men- tioned substance, must first be put into the vessels. Supposing D to be within B, the end E of an iron wire E F is to be plunged into A and F afterwards into B. As the third case shows it, F will turn under these circumstances inactive. Things being in this state, put the one end of a third common iron wire into B and afterwards its other end into A, and F will cease to be in its peculiar condition. Now, whatever the number of wires similar to that of E F may be, all their inactive ends being within B turn active under the circumstances mentioned, though they do not touch each other anywhere. Concerning the sixth case, it is obtained exactly in the same manner as stated in my letter, provided the oxidized end be replaced by one covered with peroxide of lead. Bending up the common end of the experimental wire, is, hower, not required. The best way of associating an iron wire with peroxide of lead is, to make it the positive electrode of a crown of cups (containing about a dozen of pairs of copper and zi[nk]) and to put the free end of this ware into a solution of the common acetate of lead (Saccharum Saturni) for about 8—lO minutes. By the action of the pile the peroxide is deposited on the positive iron wire. En passant I must tell you, that many reasons lead me to be- lieve, that iron associated with this substance will form the most powerful voltaic element known, and I am just about to construct out of such couples a pile. As to the chemical nature