hat current is supplied from a
voltaic apparatus,) must occur at the same moment when a common electric
discharge is passed through a long wire. Whether, if happening accurately
at the same moment, they would entirely neutralize each other, or whether
they would not still give some definite peculiarity to the discharge, is a
matter remaining to be examined; but it is very probable that the peculiar
character and pungency of sparks drawn from a long wire depend in part upon
the increased intensity given at the termination of the discharge by the
inductive action then occurring.

1118. In the wire of the helix of magneto-electric machines, (as, for
instance, in Mr. Saxton's beautiful arrangement,) an important influence of
these principles of action is evidently shown. From the construction of the
apparatus the current is permitted to move in a complete metallic circuit
of great length during the first instants of its formation: it gradually
rises in strength, and is then suddenly stopped by the breaking of the
metallic circuit; and thus great intensity is given _by induction_ to the
electricity, which at that moment passes (1064. 1060.). This intensity is
not only shown by the brilliancy of the spark and the strength of the
shock, but also by the necessity which has been experienced of
well-insulating the convolutions of the helix, in which the current is
formed: and it gives to the current a force at these moments very far above
that which the apparatus could produce if the principle which forms the
subject of this paper were not called into play.

_Royal Institution,
December 8th, 1834._

TENTH SERIES.

S 16. _On an improved form of the Voltaic Battery._ S 17. _Some practical
results respecting the construction and use of the Voltaic Battery._

Received June 16,--Read June 18, 1835.

1119. I Have lately had occasion to examine the voltaic trough practically,
with a view to improvements in its construction and use; and though I do
not pretend that the results have anything like the importance which
attaches to the discovery of a new law or principle, I still think they are
valuable, and may therefore, if briefly told, and in connexion with former
papers, be worthy the approbation of the Royal Society.

S 16. _On an improved form of the Voltaic Battery._

1120. In a simple voltaic circuit (and the same is true of the battery) the
chemical forces which, during their activity, give power to the instrume