Was Winter’s Plate Machine a Thermoelectric Device?
Was the effectiveness of the electrostatic plate machine developed by Austrian inventor Carl Winter dependent upon the thermoelectric properties of a mercury based amalgam?
The 1870 edition of Ferguson's "Electricity" (Ref.1) gives the following description of the machine's friction surfaces (or "rubbers").
"The two rubbers, one of which is shewn on the outside, in fig. 48, are
triangular pieces of wood, covered with a padding of one or two layers of flannel,
enclosed in leather, and they present a flat hard surface to the glass, so that
friction between it and them takes place in every part. They are placed in a
wooden frame on each side of the plate, and the pressure is regulated by metal
springs, fixed to the outside, between them and the frame. Before use, they are
covered with an amalgam of mercury, zinc, and tin, which is made to adhere with
the aid of a little grease, and which increases immensely the production of
electricity."
By what physical mechanism is it that the amalgam of mercury, zinc and tin
"increases immensely the production of electricity"?
Could the thermoelectric behaviour of the material be significant, and are there any other examples of mercury amalgams being used for their electrical properties?
Ref.1 Electricity, Robert M. Ferguson (pub. William and Robert Chambers, London & Edinburgh, 1870)
PS General descriptions of Winter's plate machine can be found at
http://www.uniurb.it/PhysLab/Collection_Electricity25.html
and:
http://www.hp-gramatke.net/history/english/page4000.htm
The uniurb page gives an 1873 edition of Ferguson as its primary reference.
(This page was http://book.boot.users.btopenworld.com/winters.htm )