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Wednesday Oct 4th 1843 Transverse Induction Continued _ Made the same experiment as described on the last page, with the exception that the battery of Dr Franklin was substituted for the jar, with this, the effect was not as great as with the jar. The needles were not as strongly magnetized, and those in the spirals less compounded were more intensely magnetized than the others. This result would also seam to indicate a wavey motion in the disturbance of the electrical plenum which as I suppose fills all [[space?]] [[image]] Placed a ball with the wire leading to the earth in connection with it opposite the points of the French discharger to determine if the electricity passing through the air would produce the induced current in the long wire. The result was as I expected, a strong current was exhibited by the magnetization of the needle in the spiral. [[margin]] Exp.1. [[/margin]] [[line separating paragraphs]] [[margin]] Exp.2. [[/margin]] Next the two ends of the wire of the discharger were placed in contact, so that the discharge might pass without making an explosion in the air, the same effect was produced as before, but the needles appeared a little more strongly magnetised. In the above experiments, the ball was seperated from the conductor by a plate of glass put between them. [[line separating paragraphs]] [[margin]] Exp.3. [[/margin]] The direction of the induction was not altered by changing the direction of the discharge through the discharger [[underscored]] c d [[/underscored]]. I have not yet however proved that this induction is independent of the [[face?]] electricity of the jar. [[line separating paragraphs]] [[margin]] Exp.4. [[/margin]] [[image]] Fastened by a little wax a piece of thread to the ball of the Lyden jar, and another piece to the outside. then after charging the jar the inside was touched so as to draw off the electricity until the two threads [[end page]] Thursday Oct 5th 1843 Induction Continued 57 stood at about the same angle with the axis of the jar, indicating that the quantity of free electricity in each was equal. When the discharge was made, the needle in the spiral was made magnetic, but not as strongly as with [[_]] [[margin]] Exp.5. [[/margin]] That the effect does not principally depend on the redundant electricity of the jar, is evident [[strikethrough?]] from the fact that when the jar was removed and the sparkes from the machine passed through between the points, no magnetism was imparted to the needle. [[illustration]] When the jar is discharged while standing on a cake of wax, and a wire is placed near it, the needle the [[strikethrough?]] spiral becomes magnetic the current being from the jar. Also a single spark thrown into the inside of the jar magnetizes the needle with the same arrangement as in the last experiment. NB. To prevent any direct communication of electricity from the outside of the jar, a plate of window glass was placed between the jar and the ball. [[line underscoring paragraph]] Exp. 7. [[Diagram of Leyden jar with Electrical wand on right. On left wire ab with resistor with arrow pointing upwards, while arrow pointing downwards on wand. Also written in pencil ..See page 103]] When an arrangement like that shown in the figure was made, the needle became magnetic and indicated a current in the adverse direction to that of the jar. The magnetic effect was feeble and this is what was to be expected since the return currant in the same wire would obliterate the direct, at least in part. Oct. 6 If a wire were attracted to the [[strikethrough]] conductor ab [[underscore a underscore b]]connecting it with the earth, an other effect would probably be produced, and perhaps this would be different, if the attachment were made at the top or the bottom of the conductor. [[Diagram Leyden jar with electrical wand on left, wire ab on right with resistor. a marked at bottom connection and b marked at top with a ground wire connected at a]] Tried the experiment when the wire connected with the conductor was placed at [[underscore]] a [[/underscore]], the bottom, no magnetism was developed in the needle, but when the same wire was connected with the upper part of the conductor as at [[underscore]] b [[/underscore]], a powerful developement took place showing a current upwards. Also when the discharging wire was removed, a current was produced as in exp above. [[End page]]
