in Magnetism and Electricity. 91 



each other, and is an effect entirely distinct from that which the 

 earth produces when receiving into itself a discharge of electri- 

 city, was at once made evident by lifting the saturated double 

 coil out of the canal and suspending it in the air, when the cur- 

 rent from the 5-inch quantity-armature was still sufficiently 

 powerful to make bright red-hot, at N, 15 inches of the same 

 wire which was only made warm to the touch when the naked 

 conductors were extended separately in the canal (115). 



131. That the resistance which the naked ring-electrodes 

 presented to the passage of the current from the 5-inch and 

 10-inch intensity- armatures did not arise from the circumstance 

 of their convolutions being in close metallic contact with each 

 other, was proved by the fact that the same resistance to the 

 passage of the current from these armatures (as shown by the 

 non-heating of thin wire at N) was experienced when the tape- 

 covered conductors were coiled up into two separate rings and 

 immersed in the canal at the same distance from each other as 

 were the naked ring-electrodes. 



132. Suspecting that the resistance which the two tape- 

 covered coils when separated offered to the transmission of the 

 current into the earth was due to an inductive action set up 

 among the several convolutions of each coil and operating to 

 produce a repulsion of the current on itself, the following expe- 

 riments were made for the purpose of testing the accuracy of this 

 view. 



133. Each length of the tape-covered conductors was, in the 

 first place, uncoiled, and extended in a straight line along the 

 bottom of the canal, with a lateral distance between them of about 

 20 feet. On transmitting the current from the 5-inch inten- 

 sity-armature through the conductors, a length of 2 feet of iron 

 wire *035 of an inch in diameter was made bright red-hot at N, 

 showing the passage of the same amount of current as when the 

 naked conductors were extended in the canal under like circum- 

 stances. 



134. Each of the conductors was then bent backwards and 

 forwards along the bottom of the canal in three lengths of 56 

 feet, so that the conductors were each of them in the form of an 

 elongated letter N. On transmitting the current from the same 

 armature through this arrangement of conductors, the 2 feet of 

 wire at N was made somewhat less bright red than in the pre- 

 vious experiment. 



135. Again, on binding the three lengths of each of the con- 

 ductors together with string, and immersing each of the con- 

 ductors thus folded in the canal, as shown in fig. 13, the 2 feet 

 of wire at N, though hotter than could be endured by the touch, 

 was not made visibly red-hot. 



