the Laws of Magnetic Forces. 



given distances, proportional to the powers of the inductive* 

 magnets ; but which will be further shewn. 



In the following Table is given the results of some experi- 

 ments on masses of iron similar to those before employed (15, 

 21, 22), and whose lengths were equal multiples of each other ; 

 the masses of iron being each placed in succession at a constant 

 distance from the inductive magnets, as in Figs. 5. and 9. 



The distance cd between the magnets and masses of iron was 

 made equal to three-tenths of an inch, and the distance at which 

 the induced force operated on the suspended iron #, as a b, 

 Fig. 5, made equal to two-tenths of an inch. 



In this Table, L signifies the length of the iron, and F the cor- 

 responding force of attraction, each 5 being equal to one grain. 



TABLE IV. 



26. A curious fact here presented itself in the course of these 

 experiments, namely, that, whether the masses of iron were acted 

 on through their lengths, Fig. 5, or through their breadths, as in 

 Fig. 11, still the induced force of the superior pole did not in 

 either case materially differ ; and it became further evident, 

 that, although the magnetic bar m, Fig. 11, was occasionally ap- 

 proximated within a distance of the suspended cylinder, at which 

 it could alone influence the index, yet the intervening mass ap- 

 propriated to itself the attractive power; and thus intercept- 



* I employ this term to distinguish more particularly the magnets inducing the 

 temporary development of magnetic properties in the unmagnetised iron. 



o o 2 



