92 ROYAL SOCIETY OF CANADA 

iy os 
Integrating, we get P= Lee [: eT IL 
yn CA 
and substituting for n,, P= 7 Bye [1 EVENE | 
The ionization current is proportional to the number of emanation 
atoms breaking up per secend, which is À times the number present, 2.e., 
AE: 
Hence, if i is the ionization current, i = KA P, where K is a 
constant, 
uy Wee AA 
aman ya ee [: —e ‘| Rae RR SL) L. 
If we plot a curve with ionization currents as ordinates and flow of 
air in c.c. per second as abscissae, we can see from (1) what the shape of 
the curve should be. We shall call this curve the i — ¢ curve. 
Denoting —AV as a, and —AWas 8, 
a D 
we have TRI Ne [: — € ar from which we can at once see 
that i = o when g —oor x. Ditferentiating, we get 
an 
di : < 
aia at [ce + be 
12/8 
from which it follows that 7 is maximum when 

were eeec oe eresseereossesere® A 

The curve, then, must rise from zero toa maximum, and fall off to 
nothing as the speed of the air current increases to infinity. 
