The London, Edinburgh and Dublin philosophical magazine and journal of science . h the Elliott galvanometer, and this indicateda current of about 1*3 and 1*8 milliamperes flowing throughthe resistances from the positive lamp electrode to the metalplate ; but in the case of lamp No. 2, at 48 volts the potential-difference between the platinum plate and the positive lampelectrode was only *2 volt, and this corresponded to a currentof *03 milliampere nearly. Accordingly the current is greatlydiminished when the collecting-plate is placed edgeways toand someway outside the loop of the carbon. At n
The London, Edinburgh and Dublin philosophical magazine and journal of science . h the Elliott galvanometer, and this indicateda current of about 1*3 and 1*8 milliamperes flowing throughthe resistances from the positive lamp electrode to the metalplate ; but in the case of lamp No. 2, at 48 volts the potential-difference between the platinum plate and the positive lampelectrode was only *2 volt, and this corresponded to a currentof *03 milliampere nearly. Accordingly the current is greatlydiminished when the collecting-plate is placed edgeways toand someway outside the loop of the carbon. At normalincandescence the current between the positive lamp electrodeand the middle plate when joined by the galvanometer isabout -03 or 04 milliampere when the positive leg of thecarbon is nearest the middle plate, but only about *02 or *03milliampere when the negative leg is nearest the plate. § 14. Experiment 11.—In order to compare the previousresults just given with those obtained when the collecting-plate was placed broadside to and yet outside the carbon loop, Fig. a lamp was made as in fig. 10 in which an aluminium platewas held on a platinum wire just outside one leg of the 78 Prof. J. A. Fleming on the carbon and with its plane perpendicular to the plane of thehorse-shoe. The aluminium plate was 5 ceutims. long and 1 , and distant from the nearest leg of the carbon about*5 centim. This lamp therefore differed from lamp no. 4 inhaving the plate outside the carbon loop rather than betweenthe legs. It may be noticed that in this lamp the currenthere obtained by joining the positive lamp electrode to theplate through a galvanometer was slightly greater when theleg nearest the plate was negative than when it was the positiveleg, whereas in the case of lamp No. 2 it is just the lamp exhibited also the same effect as lamp No. 4, inthat the current flowing between electrode and plate is veryliable to jump from one value to another even when thelam
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