322 



Professor Ewing on Joints 



between the curves measured parallel to the axis of «£), when 

 divided by the corresponding value of 33, is proportional to 

 the width of the equivalent gap. When this method is ap- 

 plied to the experimental results which were published in 

 the paper referred to it will be found that, for any given 

 joint, the values of *£)' — JQ are nearly proportional to 33. In 

 other words, x remains nearly constant instead of becoming 

 diminished as the magnetism is pushed towards saturation. 

 One or two instances may be quoted. 



Fio-. 1. 



15000 























14000 













13000 













12000 













11000 











CQ 10000 

 a 

 •| 9000 



s 



t i 8000 





















C 7000 













6000 

 5000 

 4000 

 3000 

 2000 























































1000 











10 12 14 16 18 20 

 Magnetizing Force due to Solenoid. 



26 28 



In Table I. experimentally found values of the magnetic 

 force due to the magnetizing solenoid are given, along with 

 the inductions observed when there was no joint and when 

 there was a joint. The joint in this case was between care- 

 fully finished surfaces, approaching the condition of true 



