ot have been then
printed; and though Signor Nobili, in his paper, has inserted my letter as
the text of his experiments, yet the circumstance of back date has caused
many here, who have heard of Nobili's experiments by report only, to
imagine his results were anterior to, instead of being dependent upon,
mine.

I may be allowed under these circumstances to remark, that I experimented
on this subject several years ago, and have published results. (See
Quarterly Journal of Science for July 1825, p. 338.) The following also is
an extract from my note-book, dated November 28, 1825: "Experiments on
induction by connecting wire of voltaic battery:--a battery of four
troughs, ten pairs of plates, each arranged side by side--the poles
connected by a wire about four feet long, parallel to which was another
similar wire separated from it only by two thicknesses of paper, the ends
of the latter were attached to a galvanometer:--exhibited no action, &c.
&c. &c.--Could not in any way render any induction evident from the
connecting wire." The cause of failure at that time is now evident
(79.).--M.F. April, 1832.

SECOND SERIES.

THE BAKERIAN LECTURE.

S 5. _Terrestrial Magneto-electric Induction._ S 6. _Force and Direction of
Magneto-electric Induction generally._

Read January 12, 1832.

S 5. _Terrestrial Magneto-electric Induction._

140. When the general facts described in the former paper were discovered,
and the _law_ of magneto-electric induction relative to direction was
ascertained (114.), it was not difficult to perceive that the earth would
produce the same effect as a magnet, and to an extent that would, perhaps,
render it available in the construction of new electrical machines. The
following are some of the results obtained in pursuance of this view.

141. The hollow helix already described (6.) was connected with a
galvanometer by wires eight feet long; and the soft iron cylinder (34.)
after being heated red-hot and slowly cooled, to remove all traces of
magnetism, was put into the helix so as to project equally at both ends,
and fixed there. The combined helix and bar were held in the magnetic
direction or line of dip, and (the galvanometer needle being motionless)
were then inverted, so that the lower end should become the upper, but the
whole still correspond to the magnetic direction; the needle was
immediately deflected. As the latter returned to its first position, the
helix and bar were agai