654 PROCEEDINGS OF THE AMERICAN ACADEMY. 



A bundle of the same size as the last (12 centimeters long and 3 

 centimeters in diameter) was then made of pieces 12 centimeters long 

 cut from Bessemer steel wire some of it 2.4 millimeters in diameter and 

 some of it twice as large. In this case the wires were not varnished 

 and eddy currents were not wholly prevented. The observations were 

 made by determining the induction flux through the central cross 

 section of the bundle, first, when the exciting current was running 

 and then after it had been suddenly destroyed. The first column in 

 Table IV. gives the strength of the field in the solenoid (47rw//10) ; 

 the other columns give, on an arbitrary scale, the flux values. 



These results represent very fairly all our experiences with bundles 

 of iron wire. Although most transformers show the von Waltenhofen 

 phenomena unless the cores are very minutely divided, I have never 

 been able to get even an approach to a reversal of sign of the magnet- 

 ism of the short packages of fine wire that I have used. One of these, 

 which was about 3 centimeters in diameter, was only 6.8 centimeters 

 long. 



In a stout iron cylinder made up of a small number of large pieces, 

 anomalous magnetism is frequently to be found. Figure 12 shows the 

 results of an interesting test upon a short cylinder of soft Bessemer 

 steel, at first solid and then slit in a milling machine lengthwise with a 

 very thin saw. The forms of the curves which show the magnitudes of 

 the anomalous magnetization in these cases are similar, but the effect 

 of the slits is very marked. 



As has been already explained, we usually opened a circuit, when 

 this had to be done suddenly, by a sharp blow upon a switch, but wo 

 experimented with other devices without finding that any of them was 



