that of Definite Combining Proportions in
Chemistry. He passed on to Static Electricity--its Conduction,
Induction, and Mode of Propagation. He discovered and illustrated the
principle of Inductive Capacity; and, turning to theory, he asked
himself how electrical attractions and repulsions are transmitted. Are
they, like gravity, actions at a distance, or do they require a
medium? If the former, then, like gravity, they will act in straight
lines; if the latter, then, like sound or light, they may turn a
corner. Faraday held--and his views are gaining ground--that his
experiments proved the fact of curvilinear propagation, and hence the
operation of a medium. Others denied this; but none can deny the
profound and philosophic character of his leading thought. [Footnote:
In a very remarkable paper published in Poggendorff's 'Annalen' for
1857, Werner Siemens accepts and develops Faraday's theory of
Molecular Induction.] The first volume of the Researches contains all
the papers here referred to.

Faraday had heard it stated that henceforth physical discoveries would
be made solely by the aid of mathematics; that we had our data, and
needed only to work deductively. Statements of a similar character
crop out from time to time in our day. They arise from an imperfect
acquaintance with the nature, present condition, and prospective
vastness of the field of physical enquiry. The tendency of natural
science doubtless is to bring all physical phenomena under the
dominion of mechanical laws; to give them, in other words,
mathematical expression. But our approach to this result is
asymptotic; and for ages to come--possibly for all the ages of the
human race--Nature will find room for both the philosophical
experimenter and the mathematician. Faraday entered his protest
against the foregoing statement by labelling his investigations
'Experimental Researches in Electricity.' They were completed in 1854,
and three volumes of them have been published. For the sake of
reference, he numbered every paragraph, the last number being 3362. In
1859 he collected and published a fourth volume of papers, under the
title, 'Experimental Researches in Chemistry and Physics.' Thus did
this apostle of experiment illustrate its power, and magnify his
office.

The second volume of the Researches embraces memoirs on the
Electricity of the Gymnotus; on the Source of Power in the Voltaic
Pile; on the Electricity evolved by the Friction o