1889.] On Time-lag in the Magnetisation of Iron, 277 



Fig. 4. 



a smaller proportion to the ultimate effect. This is well shown in the 

 following experiment (Table III and fig. 5). 



Table III. 



Magnetising 





Magnetising effect. 



current. 



f 



Additional in 









Step. 



Total. 



Immediate. 



1 minute. 





461 







15 



476 



19 



61 



13 



489 



17 



55 



11 



500 



14 



50 



15 



515 



19 



69 



.32 



547 



(41 + ) 



(142-) 



Here the last step was too large for perfect compensation. One 

 scale division of current corresponds to 0*0021 c.g.s. units of mag- 

 netising force, and one scale division of the magnetometer corresponds 

 to 0-022 of |. The immediate susceptibility to small increments of 

 force, df/djj, is now about 13. The magnetic viscosity is now so 



