1822.] produced by ElectricUy. 3 



this arc or column, having its pole at a very acute angle to it, 

 the arc, or column, was attracted or repelled with a rotatory 

 motion, or made to revolve, by placing the poles in different 

 positions, according to the same law as the electrified cylinders 

 of platinum described in my last paper, being repelled when the 

 negative pole was on the right hand by the north pole of the 

 magnet, and attracted by the south pole, and vice versa. 



It was proved by several experiments that the motion de- 

 pended entirely upon the magnetism, and not upon the electrical 

 mductive power of the magnet, for masses of soft iron, or of 

 other metals, produced no effect. 



The electrical arc or column of flame was more easily affected. 

 by the magnet, and its motion was more rapid when it passed 

 through dense than through rarified air ; and in this case, the 

 conducting medium or chain of aeriform particles was much 

 shorter. 



I tried to gain similar results with currents of common electn- 

 city sent through flame, and in vacuo. They were always 

 affected by the magnet; but it was not possible to obtain so 

 decided a result as with voltaic electricity, because the magnet 

 itself became electrical by induction, and that whether it was 

 insulated, or connected with the ground.*^ 



IV. Metals, it is well known, readily transmit large quantities 

 of electricity ; and the obvious limit to the quantity which they 

 are capable of transmitting seems to be their fusibility, or volati- 

 lization by the heat which electricity produces in its passage 

 through bodies. 



Now I had found in several experiments, that the intensity of 

 this heat was connected with the nature of the medium by which 

 the body was surrounded ; thus a wire of platinum which was 

 readily fused by transmitting the charge from a voltaic battery 

 in the exhausted receiver of an air-pump, acquired in air a mucri 

 lower degree of temperature. Reasoning on this circumstance, 

 it occurred to me, that by placing wires in a medium much 

 denser than air, such as ether, alcohol, oils, or water, I might 

 enable them to transmit a much higher charge of electricity than 

 they could convey without being destroyed in air ; and thus not 

 only gain some new results as to the magnetic states of such 

 wires, but likewise, perhaps, determine the actual limits to the 

 powers of different bodies to conduct electricity, and the rela- 

 tions of these powers. 



A wire of platinum of -^Lo* of three inches in length, was fused 

 in air, by being made to transmit the electricity of two batteries;, 

 of ten zinc plates of four inches with double copper, strongly 



'"* I made several experiments on the effects of currents of electricity simultaneous^ily 

 passing througii air indifferent states of raiefaction in the same and different directioriKH^ 

 both from the voltaic and common electrical batteries ; but I coulil not establish the fat;t 

 of their magnetic attractions or repulsions with regard to each other, which probably 

 was owing to the impossibility of bringing them sufficiently near. 



b2 



