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If two needles be fufpcnded from any given pole of a magnet 

 they will diverge, becaufe they both acquire the fame polar 

 arrangement. If a bar of iron be laid on that pole of the mag- 

 net the divergence will diminifli, becaufe the next end of the 

 iron will acquire the difpofition of the oppofite pole, and con- 

 fequently counteradl the repulfive power of the magnet. 



A MAGNET will not tranfmit its power through a bar of iron 

 if this be too long. Mufchenbruck limits their length to fix 

 feet, but this depends on the flrength of the magnet. 



The power of a magnet (every thing elfc being equal) de- 

 pends on the number of its furfaces magnetkallj arranged, and the 

 accuracy of that arrangement. 



The arrangement is accurate when the fynonimous furfaces 

 are exa^^lly parallel to each other, and originally conformed to 

 and parallel with thofe of the great general magnet. 



The magnetic attraction is ftrongeft in the direcflion perpen- 

 dicular to the magnetic furfaces, and weakens in proportion to 

 the magnitude of the angle of diredlion with the perpendicular, 

 and confequently is nu/l when at a right angle with it. Hence 

 the magnetic power feems concentrated at the poks^ and the 

 lateral powers are the weakeft, as they originate only in the 

 oblique direcjlion of furfaces, or from furfaces inaccurately ar- 

 ranged. 



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