662 Prof. F. Slate on Force-Transformation, 



into the combination 



r'T=(,r)T 1 + ir'=J .... (36) 



should be generally fruitful, under suggestion from the 

 successful analysis for Abraham's electron *. Bringing in 

 electromagnetic activity (dM/dt ) at the value which mainly 

 controls the reasoning here, 



6?M f rr m ' dv 



ai\l r rp m civ ~\ 



its divergence from (ivTi) is not such a discrepancy logically,, 

 as leaning on (^iT 1 ) exclusively would imply. Nor is its 

 removal at once compulsory, by inventing some release of 

 the electron's internal energy, for example. But concession 

 must be made to two possibilities: first that (z) is not exactly 

 equal to {y(v )) : and, secondly, that the total energy-flux is 

 greater than (i^Ti), on account of imperfect conversion into 

 electromagnetic form. We can illustrate both points by 

 returning to equation (9), put into these terms : 



= ^(1 + ^. . (37) 



If (?%) and the last parenthesis be associated, the larger 

 energy-flux denoted by the first member would appear as due 

 to a graded increase of effective inertia. The idea read into 

 Fresnel's coefficient is revived. Proceed next to revised 

 magnitudes of (/jl' , /-t), determined by an imperfect conversion 

 that leaves (in^v^j2) of (literal) kinetic energy : 



\ (3«) 



<• 

 Hence 



=f(^> 



^•>''5S=^( 1+ S)=^) ; • • (39) 



and the set (T", j*/, /* x ) grow out of (T ls jul', jj) by intro- 

 ducing the same essential factor, which equations (38) make 



* In (III.), eq. (19) to (24). We are continuing the substitution of 

 (m^) for (mo). 



