327 
Referring to § 5., it will be seen that, on Lorentz’ Theory, the equa¬ 
tion (2) of that section continues to hold provided that we take 
\*e 2 N R — lS 
ü —^ M J3 2 —J— S 2 
(13) 
In other words: if instead of (4) and (5), § 5., we regard the 
following formulae 
«=2 
e 2 N C 2 4" ^o 2 ■—■ n2 
m ’ ( C 2 -f- n 0 2 — n 2 ) 2 -j- 4C 2 n 2 
e 2 N 2 Cn 
m ' (O 2 -)- n 0 2 — n 2 ) 2 -f -4C 2 n 2 
(14) 
(15) 
as those by which the meaning of the symbols €t and & is defined, 
equations (V) and (6) of § 5. can still, on Lorentz’ Theory, be con¬ 
sidered to be true. The same conclusion applies of course to every 
result derived from equations (V) and (6), § 5.: e. g. to the relations 
(4) and (5), § 6. 
§ 11. Reverting now to the case, already examined in § 9., 
of a mono-electronic substance and collecting our results, we con¬ 
clude that, in this case, 
v 2 — 
eW F 
X m ' F 2 4 k 2 n 2 
( 1 ) 
where 
Q / e ' N 
2v x = 4n - 
m 
2hn 
' F 2 -\-4k 2 n 2 
F=n 0 2 — n\ on Drude’s Theory 
= n 0 2 — n 2 — -J 7te 2 N/m, on Planck’s Theory 
(2) 
( 3 ) 
( 4 ) 
= n 0 2 — -n 2 C 2 — -j- <y)e 2 JSf/M, on Lorentz’ Theory (5) 
where 
k — an unknown constant, on Drude’s Theory (6) 
= e 2 n 0 2 /3mc *, on Planck’s Theory (7) 
= 0, on Lorentz’ Theory. (8) 
The equations given in § 9. may also be included into the scheme: 
we have to put: 
