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[[start page]] 30 May 1st 1843 In the afternoon of this day, I made some experiments with the thermo pile exposed with its reflector attached on the radiation of [[distant?]] objects. I had at first concluded to place a [[image]] small sheet iron stove in an open field, and endeavored to determine the distance to which the [[strikeout]] [[?]] [[/strikeout]] stove might be [] and still its heat be sensible to the thermo apparatus. The idea afterwards ocurred to me to try the affect of a distant cloud. The thermoscope was at first directed towards the clear sky, when the needle moved to the side indicating a reduction of temperature and stood at 48°. The tube or rather [] reflector, was then directed to a bright cloud which was in the same part of the heavens and but a few degrees distant from the part to which the cone was first directed, the needle now stood at 25°. The experiment was made after the sun had left the cloud, with the same result, except that the difference was not now as great as before, the needle moved from 48° to 34°. When the mouth of the []reflector was lowered, so as to take in the rays from the distant horizon, then the needle advanced rapidly towards the warmer side, indicating an increased eradiation from the ground. These experiments lead me to suppose that the instrument may be improved for meterological observation by using a [] [] cone and connecting this with a straight tube blackened on the inside and highly polished on the out [[image]] make a large cone so as to fit the end of the "large reflector" use this for heat of moon. [[end page]] [[start page]] May 2nd 1843 attempt to get heat from [] action 31 1. Repeated the experiment with the magnetization of the bar of soft iron and with the same result as stated page 29. The needle [] gradually from [[underlined]] minus [[underlined]] 2° to [[underlined]] plus [[underlined]] 14°. The same experiment was tried again, and with the same result. The needle was next supposed to come to rest, and then the bar was seperated from the magnet. After the whole had attained the temperature of the room, the needle was slightly disturbed and [] through and arc of about 30°. While the articles used in the last experiment were slowly attaining the temperature of the room, I next tried an experiment with a thermopile of a single hair, for the purpose of determining if any change of temperature was produced by cappillarity. The thermopile was inserted into [[image]] the neck of a flat bottle, and the whole [] closed with a cork, so as to prevent the evaporation of the liquid contained in the phial. In this exp. I found considerable difficulty in bringing the extremity of the within the phial to the same temperature as that without. When the needle came to rest and then the phial was shaken, so as to throw the water up on the end of the pile, the needle [] to 22° degrees and then settled at about 12° on the side of the [], which indicated an increase of cold instead of heat. Repeated this and found that the needle [] [] to the [[underlined]] cold [[underlined]] side , and then by throwing up the water so as to wet the end of the pile, the motion took place in the [] [] but I afterwards found that this return was due to the heat of y fingers, acting by conduction through the glass. The causes of error in these experiments are very numerous and must be guarded against with great care. connected the coil with [] machine which was kept in action for nearly an hour, but the heat of the bar was very slighly increased. [[end page]]
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