s the name which has been given to that branch of physical science which treats of the chemical agencies of electricity, and of its influence upon the animal frame. The chemical effects of electrical action had been previously studied by Cavendish as a branch of ordinary electricity, and it was not till the year 1790, when Galvani made the interesting discovery that muscular contractions were excited in dead frogs by the contact of metals, that the new science of Galvanism was established. The boundaries of Galvanism were widely extended by the invention of the pile in 1800, by M. Volta of Como, in consequence of which the name of Voltaiic Electricity has been very generally substituted instead of Galvanism.

Had we been disposed to adopt the earlier and more popular name, and to have treated the subject under the foregoing head, the state of the science would have forced us to abandon our design. The splendid discoveries of Mr Faraday, to which we have referred in various parts of our article on electricity, have given a new form to electrical science; and as but a part of them have been published, we could only have presented our readers with an imperfect and disjointed article, the defects of which it would have been necessary to supply in a subsequent part of the alphabet. The subject of Galvanism, including Animal Electricity, will therefore be treated under the head of Voltaiic Electricity, which will contain a complete view of Mr Faraday's discoveries, as well as of those which may be made by other philosophers before that article is required for the press.