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70
Monday Oct 16th 1843

The experiment of Wheatston should be repeated and various partial conducting substances interposed, such as a tube of water, alcohol, sulphuric acid &c. Also the intensity of the discharge as well as its quantity should be varied and the effects carefully noted.

[[small circuit diagram]]
Arranged this afternoon a wire across the campus for transmitting a discharge of electricity from the Phil Hall to the well opposite our house and back through the ground [[strikeout]] from [[/strikeout]] to Mr. Clow's well at the end of the Phil Hall. The same wire had been stretched across the campus from the time of my lectures last winter, until the present, but it was taken down today and insulated at the windows of the Hall and library by [[sketched image of a tube]] placing a tube on a round stick, and over this the wire, the stick was then fastened across the window.
Also another wire for receving the induction was stretched across the campus from the Mr Maclean's well to Dr. Carnahan's. The circuit of each of these was tested by means of the galvanometer with a small single battery the negative element of which was formed of a silver thimble, and the positive of a single point of zinc plate.  At first with the wire near the old college, I found some difficulty in completing the circuit.  There appeared a break somewhere, and after considerable search, it was found at our house at a point where the wire passed behind the window shutter.  When the circuit was completed, the needle was violently agitated by the wire touching of the front of zinc to the surface of the acid - This result, which is a repetition [[END OF PAGE]]

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[[TOP OF PAGE]] Tuesday Oct 17th 1843.  71

of what I obtained last Oct., is still a matter of surprise of that [[strikeout]] the [[/strikeout]] electricity of such feeble intensity should pass through such a distance of partially conducting matter, could scarcely have been expected.

[[sketch image of a basin with two wires on opposite sides]]. An opening was made in the same circuit and a basin of rain water was introduced, the points of the wire being about 8 inches apart. It was thought that in as much as the current had passed through several hundred feet of water or moist earth, that it would exhibit but little additional diminution but in this I was much mistaken, the effect appeared to be reduced at least one half by the small addition to the resistance of the water.  This result is curious and deserves further investigation. {In accordance with the law, the earth offers little or no resistance, Dec 1845}
  The deflection of the needle of the same apparatus was considerably less when placed in the circuit between the wells of the President's and Vice President's houses. From this, it is probable that the two wells are not in aqueous connection. {Important result unless difference in the length of wire caused the difference in the effects, Dec 1845}
  The first experiment in induction with this arrangement was by sending a current through the first circuit and magnetizing a needle in the second. The magnetizing spiral was placed near the President's well and was the same which I have used before both [[strikeout]] from [[/strikeout]] for induction from an arrangement of this kind and the electricity of the clouds. The needle was strongly magnetized by a current [[underlined]] adverse [[/underlined]] to that of the battery current.
  Same experiment was several times repeated with the same result, each discharge gave indications of an [[underlined]] adverse [[/underlined]] current.