By means of the galvanic agency a variety of surprising effects have
been produced. Gunpowder, cotton, and other inflammable substances have
been set on fire; charcoal has been made to burn with a brilliant white
flame; water has been decomposed into its elementary parts; metals
have been melted and set on fire; fragments of diamond, charcoal, and
plumbago have been dispersed as if evaporated; platina, the hardest
and the heaviest of the metals, has been melted as readily as wax in
the flame of a candle; the sapphire, quartz, magnesia, lime, and the
firmest compounds in nature, have been fused. Its effects on the animal
system are no less surprising.
The agency of galvanism explains why porter has a different and more
pleasant taste when drunk out of a pewter-pot than out of glass or
earthenware; why works of metal which are soldered together soon
tarnish in the place where the metals are joined; and why the copper
sheathing of ships, when fastened with iron nails, is soon corroded
about the place of contact. In all these cases a galvanic circle is
formed which produces the effects.