( 24 ) 
We mark the elements of space with successive numbers and 
represent the components of the vectors in the rt element by fr, g,, 
h,, a, Br and y,. Let us select from an ensemble those systems whose 
data lie between the limits f, and f,-+df,, f, and f£, 4 df, … 
Jn and fy, + df, and in the same way for the other components: 
the number of these systems may be represented by: 
Ddf, «+f, dg, ---- dgn dh,....dhy da,.... da, dp, ....dBy dye dye 
or DFDE ree ee 
Here the brackets indicate, that also the other components, the 
parentheses that the same quantities also for the other elements of 
space are to be taken. We will call {(d7,)] [(de‚)| an element of 
a a: D 
extension-in-phase, 1 the density-in-phase, == the coefficient of 
probability-in-phase (.V representing the total number of systems in 
the ensemble) and 4, defined by the equation P= e%, the index of 
probability -in-phase. 
Let us consider the same ensemble after a short lapse of time dt, 
then the number of systems being ina certain phase, will have varied. 
We may conceive the variation of that number to be composed of 
12 n parts, as the systems may enter or leave a certain phase by 
passing one of 127 different limits, [(/)), [(/ + df)|, [(e,)] and 
(a, + da,)|. 
The systems passing the limit 7, contribute: 
« c vil 
df p N 
D on VION EE On dg, zee do Oh, es dr (OON SN 
3 
to the total number with which the quantity D |(/7,)| |(da,)| increases. 
The systems passing the limit 7, + df, contribute a decrease 
amounting to: 
} ee -t- 5 | D | df, | at Of weiss OR lNdat:) | So ND 
Adding these quantities we get an increase with: 
pay pul a (AF) [(de,)] (4) 
Ta Gers je axe a ates, ate ng ek 
Now we have: 
Op pe re 
Of lic? de | Òf, dt Òf, dt - 
bead. 
The second term of the second member is zero, for a depends only 
at 
on the rotation of the magnetic induction, and is independent of the 
value of f,. 
