us having the form of the couronne des tasses. The liquid used
was dilute sulphuric acid of sp. gr. 1.25. No action took place upon the
metals except when the electrodes were in communication, and then the
action upon the zinc was only in proportion to the decomposition in the
experimental cell; for when the current was retarded there, it was retarded
also in the battery, and no waste of the powers of the metal was incurred.

1002. In consequence of this circumstance, the acid in the cells remained
active for a very much longer time than usual. In fact, time did not tend
to lower it in any sensible degree: for whilst the metal was preserved to
be acted upon at the proper moment, the acid also was preserved almost at
its first strength. Hence a constancy of action far beyond what can be
obtained by the use of common zinc.

1003. Another excellent consequence was the renewal, during the interval of
rest, between two experiments of the first and most efficient state. When
an amalgamated zinc and a platina plate, immersed in dilute sulphuric acid,
are first connected, the current is very powerful, but instantly sinks very
much in force, and in some cases actually falls to only an eighth or a
tenth of that first produced (1036.). This is due to the acid which is in
contact with the zinc becoming neutralized by the oxide formed; the
continued quick oxidation of the metal being thus prevented. With ordinary
zinc, the evolution of gas at its surface tends to mingle all the liquid
together, and thus bring fresh acid against the metal, by which the oxide
formed there can be removed. With the amalgamated zinc battery, at every
cessation of the current, the saline solution against the zinc is gradually
diffused amongst the rest of the liquid; and upon the renewal of contact at
the electrodes, the zinc plates are found most favourably circumstanced for
the production of a ready and powerful current.

1004. It might at first be imagined that amalgamated zinc would be much
inferior in force to common zinc, because, of the lowering of its energy,
which the mercury might be supposed to occasion over the whole of its
surface; but this is not the case. When the electric currents of two pairs
of platina and zinc plates were opposed, the difference being that one of
the zincs was amalgamated and the other not, the current from the
amalgamated zinc was most powerful, although no gas was evolved against it,
and much was evolved at the surface