212 



EEDINOS OF Till: A.MERK AN A< A! 



The Qormal curve as determined is indicated in all these figures by 

 the dots spaced every L000 units of B. 



Figure 7 exhibits the curves taken on October 4, linn;, and shown 

 in Table III. It will be seen that these curves are very m uch flatter 

 than those of the \ in. rod and the ft in. rod which follows this one. 



4O0 



Figube '.'. [Table IV.] 



Curves Bh owing variation of magnetic induction with different lengths of ••' 

 I'm Bsemer aoft Bteel rod of diameter 0.4763 cm. The numbers affixed to the 

 curves give the constant currents in amperes through the solenoid. 



Figure 8 shows the original curves of October !>, L906, and presented 

 in Table IV. 



From the data of these curves Figure was also drawn. This showi 

 the curves of constant current as the rod is increased in length. The 

 numbers atlixed to the curves give the current in amperes, so that the 



