312 Mr HARRIS'S Experimental Inquiries concerning 



For although the cylindrical counterpoise employed in these ex- 

 periments did not admit of the forces being examined at nearer 

 approximations than those marked in the table ; yet, by substi- 

 tuting one of large dimensions, the forces may be carried on 

 nearly up to the point of contact, so as to be estimated in terms 

 of the preceding progression, since the degrees of attraction may 

 be always compared and valued in grains of absolute weight (13.) 

 In the following Table are the results of the experiments so 

 continued with the magnets d and e ; the counterpoise employed 

 being one inch in diameter, 1 of attraction corresponding to 10 

 of the former, and being equal to two grains of absolute weight. 



TABLE XV. 



It may be perceived in this table, that the corresponding forces, 

 at near approximations, do not materially vary from a simple in- 

 verse ratio of the distance. 



48. This deviation from the law of the inverse square of the 

 distance, observed in all the near approximations of the magnets in 

 Tab. 1 4. may happen, as before observed (24.), either in consequence 

 of the distant polarities having passed a certain limit, or otherwise 

 from the inductive action not going on with the same freedom 

 at some point approaching saturation. The latter would seem to 

 be extremely probable, for it has already been shown (33.), that 

 when two dissimilar polarities are opposed to each other, their 

 free action becomes more or less neutralized. In examining, 

 therefore, the inductive action upon a mass of iron be, Fig. 5. 

 (19.), the polarity d would have its free action so much reduced, 



