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July 20 1838 The screening effect did take place when the iron was placed within the helix, but the action was not as intense as when the screening arrangement was made. --------- Exp 4 on screening Performed one of the original Exp [[hand-drawn diagram]] cut plate into the [[form in the figure?]] - drew out current - found its direction the same as that of the original current. -- This Exp was devised in the first stage of the inquiry -- [[note in margin]] Catching in current from the plate --------- Exp 5 attached lon[[g]] helix to the ends of the spindle of the magneto elec machine[[?]] with the armature on for sparkes[[?]]. The 2[[superscript]]nd[[/superscript]] helix was placed within the first and arranged for shocks, no perceptible effect, but when the ribbon coil No 1 was substituted for the long helix then 2[[superscript]]nd[[/superscript]] currents were produced - Hence the same induction action takes place, between a neutral wire, and a current of magneto electricity, as between the currents of the same kind from the galvanic battery - The current under these circumstances may be called the tertiary current, since the current from the magneto electrical machine[[?]] is itself a current of induction. [[note in margin]] Secondary currents from magneto elect. ---------- Exp 6 Made a needle magnetic by the induced current from magneto electricity but the direction of the induced current was not determined by it on account of the precaution not being taken of guarding against the effect of attenuations [[end page]] [[start page]] [[begin table]] [........................]Page Northup & Galaspie.............21 Noirice[[?]] Eliphelet,........22 Notes Reviseable[[?]],.........58. Northrop Isaac....... ........63 [[end table]] Try the following exp. Put large iron into large ribbon coil and above this, placed several [[hand-drawn diagram]] plates of lead to screen the action of the lower coil. By this [[strikethrough]]we[[/strikethrough]] means, we can [[?]] the magnetic effects from the galvanic, and thus study the two seperately -- July 21[superscript]]st[[/superscript]] Tried the above Exp without Success. no shock could be obtained from the [[strikethrough]]wire[[/strikethrough]] iron with the above arrange[[strikethrough]]arrange[[/strikethrough]]ment It is however probable that the intensity of action of the iron was not sufficient to give a shock Exp 2nd Arranged third helix with rod of iron inside [[hand-drawn diagram]] put magnets in connection with each end, so as to form a magneto electrical current. A scroll of copper ribbon was then interposed between the spiral and the iron, but the same action was exhibited at the galvanometer as before. No screening[[?]] could be observed, perhaps the action was due to the ends of the iron and these were [not?] covered by the copper. [[note in margin]] May 12[[superscript]]th[[/superscript]] 1839 See Exp of this date This exp. illustrates the importance of Regersting[[registering?]] all the facts observed within[[?]], in accordance or not with previous results since - I now find that there is a remarkable difference in the action of this arrangement and the other cases of screening. -------------- Exp 3 Placed plate of Zinc between coil No 2[[? smudged]] n[[?]] 2 needle [[?]] slightly[[?]] magnetice[[?]] withdrew Zinc. needle strongly magnetic, screening only partial, as [[?]]al action in the same direction with the battery current Repeated Exp of [[J C Henry?]] between 2 & 3 and current [[end page]]
