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6
Oct 6th 1842 } Experiments on the induction of the long wire and other parallel wire

Sufficient to send a current through
feet of wire and     feet of earth

[[sketch of wire routing from philos hall to my study]]

The above sketch will serve to
give an idea of the arrangement.

Oct 7th
Made a number of experiments to day
with the the wire above described, and another
placed parallel to it.  A discharge [[overstrike**]] went [[**end overstrike]]
of
electricity from 3 jars of the French [[battery?]]
was passed through the wire, and a needle
placed in a helix connected with the secondary
wire was magnetized.  The arrangement
was as follows.  Two poles, supported by tripods
formed of long slats of boards, were placed upright
in the back campus, and over the tops of these
a part of a wire was stretched parallel to the wire
through the old college, and of a length equal
to the whole breadth of the campus.  This wire was
continued backward on each side, until
it extended to the two halls, it then crossed over
with the two ends united, so as to form a complete
parallelogram.  In the first experiment, the
distance of the [[means?]] and parallel parts of the
two wires was 60 feet, and with this the needle
placed in the helix used in the study for atmospheric
electricity, was strongly magnetized.
     The parallel part of the second wire
was next removed to the distance of 90 feet from
that of the wire through the old college, and

[[NEW PAGE]]
                                   7
Oct 7th 1842  }  Induction of ordinary
                 electricity [[overstrike**]] at [[**end overstrike]]
at a great distance

again at this distance several needles were magnetized
to a degree scarcely less than in the case of
the least distance.  In the experiments previous
to the one now to be mentioned, the electrical
discharge was from three     jars.
     The charge was now reduced to that
from one jar, the needle again came from
the helix strongly magnetic.
     Next, the jar was removed, and a single
spark thrown on to the suspended end of the
conducting wire, while the other end was connected
with the rubber.  The needle with this
was also magnetic but apparently not quite as 
strongly as before.
     After this, the second wire was removed
from the long poles, and the parallel part
stretched between the two upper windows
of the first entry of the two parallel colleges.
By this arrangement, the distance between the
parallel parts was increased to 165 feet
but not withstanding this great distance, the
needle from the induction of a discharge of
3 jars was strongly magnetized.  The experiment
of a single spark was not attempted on account
of the lateness of the hour.
     It would appear
from the strength of the inductive action that
at this distance, that the space between the
two wires can be further increased.
     The needles in all the above mentioned experiments
were magnetized in the same direction, indicating
a current in     of the running current