What is Thermo-electricity?

If two bars of any unlike metal--for example, antimony and bismuth--be
soldered together at one end, and the other ends be connected by a
wire and then the soldered end heated, a current will flow.


What effects are produced by currents?

They produce heat, light, decomposition and combination in liquid
chemical compounds; they melt all metals, excite magnetism, and in the
animal body excite movements of the muscles.

Can you specify these effects?

A strong battery produces heat in such a degree that all metals can be
melted. Light is produced in flashes, or if the end of the leading
wires are connected with two pencils of hard carbon, and brought very
near together, then a brilliant light, or arc, called the voltaic arc,
is produced. This is the dazzling bright light which we call electric
light. The chemical effect of a current in decomposing compound
substances is called electrolysis. In this way water can be decomposed
into its compounds, hydrogen and oxygen; copper sulphate into sulphur
and metallic copper, etc. In this way we can deposit strong adherent
films of metal on the surface of any conductor; for if the article to
be coated be attached to the negative electrode of a battery, and
dipped into a solution of the metal with which we desire to coat the
article, say copper or silver, and the positive electrode be attached