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PROCEEDINGS OF THE AMERICAN ACADEMY 



b. The Magnet. 



Table IV. gives the distribution for a hollow tube of soft iron (one 

 metre in length) magnetized by a core of steel wires extending half 

 way down the tube. The magnetism was obtained by halving the 

 difference of the two values obtained before and after reversing the 

 magnetic core. 



TABLE IV. 



HOLLOW TUBE WITH MAGNETIC CORE. 



Last of all, let us examine the case of two magnets joined by their 

 opposite poles. 



* That is the distribution of tlie permanent magnetism of the armature upon 

 the magnet. 



