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32 May 2nd 1843  [[boxed in]]Heat from the magnetization of iron[[end of box]]

[[image in left margin]] Made a new arrangement of the apparatus for seperating the small bar from the keeper, this consisted in fastening the bar across a hole in a small board, and placing this on the magnet inverted. The board is elevated or depressed when the bar is to be brought in contact with or seperated from the magnet. When the bar was seperated from the magnet, the needle moved about 2 1/2° to the [[underlined]] cold [[/underlined]] side.

Also when the needle was again suffered to come to rest, and the bar was suddenly brought into contact with the magnet, the needle again moved to the [[underlined]] cold [[/underlined]] side about 2° degrees. These experiments would appear to show that no heat is produced by the magnetization of the bar, and that the effects I obtained before were due to the friction of the pile on the surface of the bar. The last arrangement was such as to prevent any rubbing, and also to lessen the effect of percussion.

[[underlined]] May 3rd [[/underlined]] When the same exp. was repeated this morning, the needle again moved to the [[underlined]] cold [[/underlined]] side about 10°. These changes appear to be owing to the difference of temperature in the thermo pile, and the magnet, the latter being large and consequently requiring considerable time to assume the temperature of the [[circled]] circumambient [[/circled]] while the former being small soon feels each change of temperature.

Try this exp. with a long bar and a coil, one end of the former being thrust into the latter, the pile at the further end.
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May 3rd 1843  33

[[image]] Made an experiment to day to determine the polarization of a conductor, when a current of galvanism is passing through it. It is well known that when a current is passed from the circumference to the centre of a wheel, or in the opposite direction, that motion will be produced in the wheel, provided a magnet be placed on each side of it. Now this effect could not take place according to my view of the phenomenon, unless there was a degree of persistence in the direction of the current. It was with the intention measuring this persistence that this experiment was instituted.  The apparatus was however too heavy to exhibit any effect even if it existed, since no motion was produced by placing a powerful horse shoe magnet on the plane of the axis of the plate.

 I intended to give motion to the plate, supported as it was on friction [[strikeout]] [[soles?]] [[/strikeout]] by means of a small weight [[strikeout]] passing over [[/strikeout]] suspended from a string suspended over an axle. The friction was so great that no difference in the velocity could be observed, wether a current was passing or not. When however the the magnet was placed with its legs on each side of the wheel, the force of persistance was sufficient to stop the descent of the weight.

 Next tried to get indications of[[strikeout]]rom[[/strikeout]] heat from the magnetization of a bar of soft iron - For this purpose the bar was placed in the lecture room, at the distance of 27 feet from the galvanometer; yet at this distance the needle was slightly affected with the polarity of the bar, and in the direction which would indicate heat when the pile was connected. The result of the exp. was very unsatisfactory. the heat if any was developed could not be eliminated from that of the galvanic current around the iron, and the difference of temperature of the bar and the pile.

Transcription Notes:
antiquated word: http://www.merriam-webster.com/dictionary/circumambient