76 NOMOS. 



of a centripetal force, and thus rotation would be 

 nothing more than an accident connected with the 

 form of the apparatus. But if the magnet is set in 

 motion in a resisting medium, by an impulse which 

 is subtensial in its character, it follows that it must 

 move eventually in a circular orbit around the con- 

 ductor, or rather in a polygonal orbit which cannot 

 be distinguished from a circle. In the first instance, 

 the magnet may be carried by the impulse beyond 

 the circle which would pass through its first position, 

 but if it is so at first it is not so always. It is not 

 eo always, because the impulse fails as the distance 

 from the conductor increases, until at last the impulse 

 and resistance are so counterbalanced, that the 

 magnet is carried into the circle which passes through 

 the point from which the impulse last originated. 

 And when this happens, the magnet must enter upon 

 a circular, or quasi circular path, for the impulse can 

 undergo no change so long as the distance from the 

 conductor remains the same ; and the distance must 

 remain the same if the magnet is continually moved 

 to different points in the same circle. The same re- 

 sult must also follow, if, on the other hand, the impulse 

 is not sufficient to overcome the resistance so as to 

 maintain a movement in a circular orbit; for in this case 

 the magnet must continually approach the conductor 

 by stopping at points within the circle, until the in- 

 crease of impulse which is derived from the decrease 

 of distance is sufficient to overcome the resistance 

 and carry the magnet to the same distance from the 

 conductor as it was when the impulse originated, 

 and then, for the reasons already given, the movement 



