SHUDDEMAGEN. — DEMAGNETIZING FACTORS FOR IRON RODS. 223 



first solenoid. But as the reversal method has now almost overtaken 

 the step method, we may conclude that both are very nearly at their 

 limiting positions, reached for very slow establishment of the magnet- 

 izing field, which are probably very nearly the same. 



TABLE XI. [Figure 13.] 



January 18, 1907. 

 Diam. = 1.111 cms. = 7/16 in. 

 Step Method. Long Coil. 



Figure 15 gives the original curves of Table XIII, taken on February 

 21, 1907, and following. As it was found that in the long solenoid 

 the reversal method gives us practically the same results as the steps 

 method, it was now used throughout because of its convenience and 

 accuracy. Compared with the results of the rod of " cold rolled shaft- 

 ing " these values are somewhat smaller, but not more perhaps than is 



