rvening plate (1011.), fig. 92, when a
few drops of nitric acid were added to the contents of cell ii, then the
current of electricity passed with considerable strength (though it soon
fell from other causes (1036; 1040.),) and the same increased effect was
produced by the nitric acid when many interposed plates were used.

1021. This seems to be a consequence of the diminution of the difficulty of
decomposing water when its hydrogen, instead of being absolutely expelled,
as in the former cases, is transferred to the oxygen of the nitric acid,
producing a secondary result at the _cathode_ (752.); for in accordance
with the chemical views of the electric current and its action already
advanced (913.), the water, instead of opposing a resistance to
decomposition equal to the full amount of the force of mutual attraction
between its oxygen and hydrogen, has that force counteracted in part, and
therefore diminished by the attraction of the hydrogen at the _cathode_ for
the oxygen of the nitric acid which surrounds it, and with which it
ultimately combines instead of being evolved in its free state.

1022. When a little nitric acid was put into the exciting cells, then again
the circumstances favouring the transmission of the current were
strengthened, for the _intensity_ of the current itself was increased by
the addition (906.). When therefore a little nitric acid was added to both
the _exciting_ and the _retarding_ cells, the current of electricity passed
with very considerable freedom.

1023. When dilute muriatic acid was used, it produced and transmitted a
current more easily than pure dilute sulphuric acid, but not so readily as
dilute nitric acid. As muriatic acid appears to be decomposed more freely
than water (765.), and as the affinity of zinc for chlorine is very
powerful, it might be expected to produce a current more intense than that
from the use of dilute sulphuric acid; and also to transmit it more freely
by undergoing decomposition at a lower intensity (912.).

1024. In relation to the effect of these interpositions, it is necessary to
state that they do not appear to be at all dependent upon the size of the
electrodes, or their distance from each other in the acid, except that when
a current _can pass_, changes in these facilitate or retard its passage.
For on repeating the experiment with one intervening and one pair of
exciting plates (1011.), fig. 92, and in place of the interposed plate P
using someti