335 
, h 
“+P- 
Now equation (3), § 15., may be written 
»(— D- 
( 6 ) 
( 7 ) 
since A^/A in Scheel’s experiments ranges from about ^ to about j- 
(as will be seen from the value of A 0 presently to be given) we 
bave, as a first approximation, 
D = 3/2a ; A=z3b/2a 2 . 
( 8 ) 
For hydrogen, Scheel’s values of the constants are, when expressed 
in the units here adopted: 
a = 1358,3 . IO“?; & = 9 . 05 . 10-«. 
Substituting in (8) we obtain 
D = 11043 
A = 7,36. 
( 9 ) 
From Mascarf s data x ) we arrive at results which are out of 
harmony with the foregoing ones; for instance, from 
a) A = 5,085 
b) 
.438 
v = 1,0001392 
1383 
we find 
A = 4,82' 
( 10 ) 
We can by the aid of the preceding results easily calculate the 
value of the dielectric constant of hydrogen. If we take o = 0 
equations (6), § 9., and (4), § 15., show that 
gD = l (11) 
so that equation (4), § 13., becomes 
(K-1)(D-1) = 3. (12) 
The following shows the values of K corresponding to some of the 
values of D found above: 
0 Taken from H. Dufet, Recueil de Données Numériques, Optique, 
Paris 1900, p. 75. 
6 * 
