308 Mr HARRIS'S Experimental Inquiries concerning 



stanced as before explained (42), does not, at all distances, exert 

 an inductive influence proportionate to its power on unmagne- 

 tised iron. 



In the following Table are given the results of two series of 

 experiments with magnets, whose inductive powers on unmagne- 

 tised iron were as 2 : 1 ; and it will be seen that this ratio is not 

 the same at all distances from the magnetised steel. The mag- 

 nets are denoted by A and 2 A, placed over the respective forces 

 of induction ; D being the corresponding distance. 



TABLE XIII. 



These experiments shew that a variety of cases may exist in 

 which the intensities of the magnets become so circumstanced, 

 in relation to each other, that the inductive action no longer 

 proceeds. 



45. The absolute attractive or repulsive force exerted be- 

 tween two magnets at various distances, will materially depend 

 on the operation of the inductive influence, the induced forces and 

 the distances being both variable ; for we have already seen (39.), 

 that the absolute force exerted between a magnet and a mass of 

 iron, varies with these quantities conjointly. The same may 

 therefore be inferred of the absolute force exerted between two 

 magnets ; for a very little reflection will serve to show, that, in 

 estimating the absolute force exerted between them, it is still 

 the same compound action which we measure (39). Thus, as 

 already observed, when only one of the bodies B, Fig. 6. is per- 

 manently magnetic, the absolute force is directly proportional to 



