I87I.] 



Electricity. 



121 



unimpeded ; on attempting to get out of the magnetic field it experienced the 



same resistance as in the first part of its fall. The ring was seven seconds in 



falling through the two inches of magnetism. 



But on breaking the soldered junction, k, of the ring, a, and thus preventing 



the formation of electric currents therein, the ring, to all appearance, fell 



between the poles as rapidly as 

 Fig. 27. if there had been no magnetism 



there at all. Therefore, electri- 

 city, which has no weight, 

 actually helped to keep the 

 heavy metal copper in suspen- 

 sion in the air, notwithstanding 

 the attraction of gravitation. 

 Mr. Varley concludes from this 

 experiment that " a current of 

 electricity is as solid and material 

 to a magnetic field as is a plate 

 of iron to a bar of copper." 

 The following is another 



curious experiment made with Lord Lindsay's large magnet. A horizontal 

 piece of vulcanite, v, was placed between the square poles, n s, Fig. 28. An 

 end view of one of the poles, with the vulcanite, v, is shown in Fig. 29. When 

 one of the copper rings was placed rather more than half way in between the 



Fig. 28. 



Fig. 29. 



X 



t-l 



poles, as in the cut, the magnetisation of the magnet drew the ring inwards. 

 When the ring was a little less than half way in, as shown by the dotted lines, 

 the magnetisation of the magnet repelled the ring. Although the movement 

 of the ring was not more than § inch, yet there was power enough to roll it up 

 an incline of thirty degrees. 



Another experiment made by Mr. Varley is shown in Fig 30. Two hollow 



Fig. 



30. 



^ 



3 B 



poles were placed upon the magnet; when the magnet was not magnetised, 

 and a burning taper, a b, was thrust in until the burning wick was opposite 

 the opening between the poles, sufficient air did not pass between them to 

 support combustion, and the flame was extinguished after burning a few 

 seconds. On the other hand, when the poles were magnetised, and the taper 

 vol. viii. (o.s.) vol. 1. (n.s.) r 



