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of steel and placed it beside the magnet, after which it sus- 

 pended a small key.] There was there a less tendency to 

 get magnetism by juxta-position than in iron, but there was 

 a greater tendency to retain it. For whilst the iron lost its 

 power by removal from the magnet, the steel did not. The 

 more imperfect the iron, as in ores having perhaps one-third 

 or two-thirds, or five-sixths of earthy substance, or the more 

 it was in a state of oxide — the less were its capabilities for 

 showing the magnetic action. If they took cast-iron, they 

 would find a susceptibility of the magnetic influence, but in 

 a degree of capability very different from that of malleable 

 iron. If they took malleable iron, of a quality pure and 

 soft, they would find the highest capacity for the magnetic 

 condition. Now, when he discovered that any portion of 

 ferruginous substance in a body rendered that substance 

 capable of magnetic development, and when he knew that 

 malleable iron generally exhibited that in the highest degree, 

 then he drew the inference that that which was most perfectly 

 iron would show the highest development of the magnetic 

 condition ; and, therefore, that the iron which should exhibit 

 the highest magnetic capabilities would be the best quality of 

 iron. There were two methods by which, on these princi- 

 ples, they might determine the quality. [The Reverend 

 Gentleman then placed upon a stand a magnetic needle or 

 compass, having at the end a small graduated card as a scale. 

 He then took up a small flat magnet and two small flat pieces 

 of iron.] He had there two pieces of iron from the Bowling 

 Works. They were marked B and L — B being the mark for 

 the best iron, and L iron of the lowest quality. He had also 

 a superior steel magnet of the same size. [He then opposed 

 the magnet steel bar to the compass at some distance, and 

 placing in succession upon it the iron plates B and L, he 

 found that the needle receded from the magnet with L upon 



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