SHUDDEMAGEN. — DEMAGNETIZING FACTORS FOR IRON RODS. 221 



observation-points at quite a distance off. Most of the other curves 

 are in much better agreement with their points. There were also 

 taken a number of magnetization curves for the initial length of the 

 rod, 15 feet, which made m = 329 ; these curves resembled the ones 



TABLE IX. [No Figure.] 



December 1, 1906. 



Diam. = 0.6350 cm. = 1/4 in. 



Reversals. 



for the rod with pronounced consequent poles. It thus appears that 

 there must have been some irregularity in the demagnetized rod near 

 one or perhaps both ends of the rod. As the rod was cut down from 

 m = 329 to m = 200, most of these irregularities were cut off. Then at 

 the next shortening practically all the rest was eliminated. For m = 30 

 a reversal curve, represented in the figure by crosses, was also taken. 



