304 Mr HARRIS'S Experimental Inquiries concerning 



The following are the results of two series of experiments, in 

 which the distances and forces were compared by decrements of 

 the tenth of an inch, and it will be perceived, that the trifling 

 irregularities occasionally observed in some of the numbers, are 

 not of such importance as to leave any doubt concerning the law 

 we have been endeavouring to determine, and are, besides, in 

 many instances not appreciable by the instrument. In these ex- 

 periments, two magnets were employed, designated by A and B, 

 and were such as to ensure, as far as possible, accurate results, 

 the conditions before explained (17) being fully considered: D 

 signifies the distance between the iron and magnet, and / the 

 corresponding force of attraction ; the distances being adjusted 

 by the apparatus before described (10). 



TABLE X. 



Showing the Attractive Force of a Magnet and Iron 

 on each other at various distances. 



40. The law observable in the preceding experiments may be 

 generally observed by approximating the pole of any magnet to- 

 ward the suspended iron x, whether a small cylinder of precisely 

 the same dimensions, or otherwise a powerful magnet of any form 

 and length. The variation in the angles at which the attractive 

 force of the latter may be supposed to act on the suspended iron, 

 where the opposed surface is more extensive, not having for a 

 short distance any material influence in disturbing the uniformity 



