the Laws of Magnetic Forces. 



299 



TABLE VI. 



TABLE VII. 



35. In these, as in the former experiments (32. 37), the ef- 

 fect produced on the index was quite independent of the dimen- 

 sions of the iron, and was observed to be nearly the same, 

 whether opposed to the magnet m through its length, as in Fig. 

 13, or through its breadth, as in Fig. 14, the proximate induced 

 polarity of the iron appearing to be in each case alike. Similar 

 results were also obtained to those before noticed (24), in em- 

 ploying magnets of powerful intensities ; it being observable, 

 that, at very near approximations, the effect on the index was 

 not precisely proportional to the powers of the magnets. 



36. The general results of the foregoing experiments (34) 

 became further shewn, when the magnetic forces employed were 

 those induced in a mass of iron, as in Fig. 15. Thus, a mass of 

 soft iron da, not exceeding three inches in length, being placed 

 with one of its extremities immediately under the suspended 

 cylinder #, a magnetic bar bm was opposed to its opposite extre- 

 mity a, so as to induce in the iron a magnetic developement ; 

 the number of degrees of attraction, and the distance of the cy- 

 linder x, being noted, a second and similar mass of iron en was 

 then opposed to the induced pole ; and thus, by making the dis- 

 tance a b always the same, and varying the distance c d, the mag- 

 netic developement in da remained the same, whilst the dis- 

 tance of the opposed iron n c became variable ; and by making 

 distance c d always the same, and varying a b, we are enabled to 



VOL. XI. PART II. 



p P 



