(1) Mr. Clerk Maxwell has recently published an exceedingly
important investigation connected with this question. Even
in the non-mathematical portions of the memoirs of Mr.
Maxwell, the admirable spirit of his philosophy is
sufficiently revealed. As regards the employment of
scientific imagery, I hardly know his equal in power of
conception and clearness of definition.

(2) One important difference, of course, exists between the
effect of motion in the magnetic field, and motion in a
resisting medium. In the former case the heat is generated
in the moving conductor, in the latter it is in part
generated in the medium.