SHUDDEMAGEN. — DEMAGNETIZING FACTORS FOR IRON RODS. 219 



for consequent poles before they were bought for the work. Even then 

 some peculiarities were noted in the results, which are due to some 

 irregularity in the polarity which was not apparent in the test with a 

 small compass needle. It should be noticed that such irregularities as 



TABLE VII. [Figure 11.] 



November 16, 1906. 



Diam. = 0.3175 cm. = 1/8 in. 



Step Method. 



shown in Figure 12 are very mach more pronounced when the step 

 method is used. In fact, with the reversals it would probably turn out 

 that a very smooth curve would be obtained, but which would lead to 

 erroneous results in the demagnetizing factor. 



No figure is given for the series whose results are tabulated in 

 Table X, of January 16, 1907. This table should be compared with 



