92

DOC.

127

NOVEMBER

1908

Number of molecules N

=

n

=

number of

free,

negative

electrons

(with oo

small

radius)

that

are

also

present.

Interaction

between

molecule and

electron:

1.

As

long

as v

(vel.

of the

electron) G,

the

latter

recoils from

the

molecule

elastically.

2.

As

long as v

G,

the electron

penetrates

into the

molecule,

ionizes

it,

since

the

bound electron

is

ejected

with

the

identical,

and

identically

directed,

velocity

v-and the

first

electron

thereby

gets

bound

in the

molecule, i.e.,

for

v

G,

the influence of the

collisions

can

be left

out

of consideration.

The

change

in

the number of electrons

in the volume

element dr

&

veloc.

region

dw,

will thus be

v

G

for

v

G

v

G

dZdZ

=

0

if I

assume

with Lorentz

that[3]

dZ

=

-irNR2^

-vx(v)dw.dc

=

0

f

=

A.e-hv2

+

gX(v)

where

X(v)

must

always

remain

very

small.

From

this it

follows[4]

v

G

f1

=

Ae-hv2 +

1-L-

(2hAX-dA+V2Adh-dx)e-hv2dx

nR

N

v

G

f2

=

Ae~hv2

This

then

yields

the earlier

expressions

furnished

with

different

factors.

Yours

most

respectfully,

P.

Gruner