^ iU. 



THE NATURE OF ELECTRICAL DISCHARGE- 

 POSITIVE COLUMN EFFECTS IN A 

 METAL CONDUCTOR. * 



Francis E. Nipher. 



In former papers in these Transactions (Vols. XIX No. 

 1; XIX No. 4; XX No. 1) experimental evidence lias 

 been obtained, which seems to indicate that the positive 

 column or the positive streamers in electrical discharge 

 through gases, is a negative inflow to the exhaust or 

 positive terminal. The molecules of matter in such a 

 drainage channel are moving in the opposite direction 

 from that in which the negative fluid is flowing. 



The result of recent experiments with solid conductors 

 seems to justify the conclusion that such a conductor 

 carrying a discharge, is an aggregation of positive ions, 

 and that a copper wire under such conditions is urged 

 in the opposite direction from that of the corpuscular 

 flow. 



A wire 50 centimeters in length and having a diameter 

 of 0.23 mm. was placed in a glass tube supported at its 

 middle point in a horizontal position. Tubes of various 

 internal diameters between one and five mm. have been 

 used, and all give similar results. The length of the 

 tube is such that the wire protrudes from it at each end 

 a distance of about a centimeter. 



Two discharge knobs fomiing the terminals of rods 2.5 

 meters in length were placed with their centers over the 

 ends of the glass tube. The rods were supported near 

 the glass tube by silk cords. The other ends rested on 

 the discharge rods of an eight-plate influence machine, 

 driven by an electric motor. The glass tube containing 

 the wire was parallel to the discharge rods of the ma- 

 chine, and at right angles to the rods leading from the 



*Presented June 3, 1912. 



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