ELECTRICAL AND MAGNETIC DISCOVERIES OF FARADAY 641 



vanometer, and he found that it was magnetized by this electrical wave, 

 at the moment of making or breaking the main circuit. 



But Faraday was not content until he had discovered all the laws 

 of this new action; he placed two wires on boards, so that, when near 

 together, they were parallel to each other. He now found that the 

 action took place, not only when the current was interrupted, but also 

 when one wire was moved with respect to the other. 



So far, the new effect had only been obtained near an electric current. 

 But Faraday did not forget the connection between electricity and 

 magnetism, but now proceeded to give a new aspect to his discovery. 



For this purpose he chose a ring of wrought iron on which he wound 

 two coils of wire which he attached to a battery, and to a galvanometer, 

 as before. From the presence of the iron, however, he obtained an 

 immensely greater effect than at first, so that, instead of an almost 

 microscopical deflection, the needle of the galvanometer whirled around 

 three or four times, and on attaching two points of charcoal to the ends 

 of the secondary wire, he observed a minute spark between them on 

 completing the main current. The same increased effects occurred on 

 placing bars of iron in straight coils of wire, and Faraday had now 

 proved that the new effect was dependent on the magnetic action of 

 the current. 



He now made one step further, and showed that these induced cur- 

 rents could be obtained from permanent magnets without the aid of 

 other currents, by the simple motion of a wire near a magnet, and that 

 they were specially intense when the wire was wound on a soft iron 

 cylinder, which was then moved near the poles of a magnet. Not con- 

 tent with observing these currents by a galvanometer, he obtained a 

 powerful permanent magnet and allowed his bar of iron, wound with the 

 coil, to come in contact with the poles, the circuit being broken at the 

 same instant. A spark was observed at this broken junction every time 

 the bar came down on the poles. Tyndall tells a very curious story of 

 this experiment which we can well recall. Faraday was attending a 

 meeting of the British Association in Oxford, in 1832, and was re- 

 quested to show some of his wonderful results to the scientists there 

 gathered. While he was thus occupied a dignitary of the University 

 entered and inquired what was going on. Prof. Daniell, who was 

 standing near, explained the matter in popular language. The Dean 

 listened with attention, and looked earnestly at the brilliant spark, but 

 a moment afterwards he assumed a serious countenance, and shook his 

 head: " I am sorry for it," said he, as he walked away; " I am sorry for 

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