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PROCEEDINGS OF THE AMERICAN ACADEMY 



Table VIII. shows the manner in which the mean position of the 

 diaphragm varies when the magnetizing current is increased. There 

 is no current flowing through the line coil. The distance of the dia- 

 phragm from the core with no magnetizing current flowing was T £ F 

 inch. 



Rogers Laboratory of Physics, 

 June, 1892. 



