and Phenomena of' Magnetic Induction. 2G9 



Hence the ratio of influence on the soft iron-bar \ of an inch 

 thick (l:)eing precisely of similar dimensions to those of the mag- 

 net) was as follows, nearly : At the distance of 5 inches, the 

 iron-bar acquired y^^th of the power of the magnet ; at 4 inches 

 distance the inductive influence of the magnet, was /gth of its 

 own power ; at 3 inches ^'yth ; at 2 inches i^th ; at 1 inch Jth ; 

 at Jth of an inch \ ; and at ^^^th of an inch f . 



But the proportional influences at the various distances will 

 be more evident, by a reference to the annexed additional Table 

 of deductions^ from the middle series of experiments made with 

 the quarter-inch bar, which was similar in all its dimensions to 

 the magnet. 



Deductions from Experiments with the bar of soft iron 13| inches long 

 by 1 inch broad and \ inch thick, and Magnet of same size. 



The last column of this table represents the proportionate 

 force of the induced magnetism at the several distances of 1, 2, 



