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[[Start Page]] 54 Tuesday Oct 3rd 1843 Does ordinary elect pass along the surface? Made a series of experiments to determine whether ordinary electricity in passing through a conductor passes on the surface, or through the entire mass. For this purpose, a spiral was made of a number of turns of a piece of bell wire and this was placed with a needle in it in the axis of [[image- tube with line running through it, line/wire spiraled in the center of the tube and straightened again to end]] a hollow iron tube and a shock from a single jar sent through the tube, but the needle exhibited no signes of magnetism. The same wire and spiral were next placed on the outside of the tube, the shock again passed, and now the needle was found to be magnetic. The experiment was repeated by substituting a tube of tin foil around a paper cylinder, the needle spiral and connected wire being placed in the inside. The needle exhibited no signes of magnetism, but when the needle and spiral were arranged on the outside, magnetic effects were produced. The intensity of the charge of the battery was about the same in the different experiments. The discharge was from a single jar highly charged--with a larger battery less highly charged the effect would probably was different. [See American Endycopedia Dobsons Edition] Repeat this exp with battery of several jars less highly charged, ___ Also with galvanism the wire soldered to the tube. [See Exp of Mr Kennedy, I think in the Phil Mag Irish academy] [[Written on side of sheet with line leading to this part of text]] The surface alone is not however to be considered in erecting lighter rods. [[underlined]]Made an other experiment. [[/underlined]] Put sulphate of pottassa in cup of water, introduced under the surface of the same two insulated ends of wires, sent shock through water from single jar, The salt became luminous and was broken by the concussion of the water. [[end of page]] [[New page]] Wednesday Oct 4th 1843 Lateral Induction. Ordinary Electricity 55 Water appears to conduct electricity badly, and when a large quantity is to be transmitted, the effect is the same as that of sending a discharge through the air. Try if the same noise and projection of the water would be produced, which I observed in this experiment when the discharge is made between two plates of [[water? metal?]]. [[image- battery created with bottle on wax, wire leading from top of bottle to wire suspended on flat platform, other end of wire leads to wax circle on bottom of bottle. Tube around wire on platform has spiral lines leading from center out]] Sent charge through the horizontal wire a b, while a ball c was placed at a small distance from the circuit and seperated from it by a tube of glass which surrounded the wire. The jar was insulated, so that the inside or outside could be rendered redundant at pleasure. In all cases induction was produced in the wire c d, which was connected with the earth at its lower end, or rather was united to a wire which passes out of the window and is soldered to a copper plate buried in the earth. The current was from the horizontal wire towards the earth, both when the outside had the redundant electricity and when it was deficient. In one experiment the most compounded of the three spirals used gave the needle the least degree of magnetism of the three, and this would seam to indicate that action consists of an oscillatory motion, or that there is an action and a reflex action. In another experiment, a spark passed from the horizontal wire to the ball c and then the current as indicated by the magnetization of the needles, was towards the horizontal wire, of this however I am not very sure. To prevent the passage of the electricity from the wire to the ball, the glass tube was employed. [[end page]]
