590 DOC. 62
DISCUSSION
OF
HASENÖHRL
Published
in
Physikalische
Zeitschrift
10
(1909):
830. Discussion
following
Hasenöhrl
1909a,
held
on
21
September
1909,
published
10 No-
vember
1909.
[1]
Friedrich
Hasenöhrl
was
Professor
of
Phys-
ics
at
the
University
of
Vienna. He
was
well
known
for
his studies
of
electromagnetic
radia-
tion, especially
Hasenöhrl 1904.
In his talk,
Hasenöhrl
1909a, Hasenöhrl
reported
the
re-
sults
of
calculations
of
the resistance
experi-
enced
by
various models
of
molecules when
they
move
through a
field
of
radiation
uniformly
distributed in all directions. He concluded
that,
if
a gas
of
such molecules
were
enclosed in
a
container
filled with radiation,
"the
kinetic
en-
ergy
of
the molecules will
...
be transformed
gradually
into
radiation-this
transformation,
however,
will take
place so slowly
that the usual
gas
laws
...
are
not altered
in
a
noticeable
way.
The
change
of
the radiation,
in
terms
of
percent-
age,
will in
general
take
place
much
more rap-
idly"
("Es
wird sich
...
die kinetische
Energie
der
Moleküle allmählich in
Strahlung verwan-
deln-diese
Umwandlung
wird aber
so langsam
vor
sich
gehen,
daß die
gewöhnlichen Gasge-
setze
...
nicht in
merkbarer
Weise alteriert
werden. Die
Veränderung
der
Strahlung
wird im
allgemeinen prozentuell
viel rascher
vor
sich
gehen")
(p. 830).
Hasenöhrl
1910 is
a
fuller
ac-
count
of
this
work.
[2]
Einstein had
considered this
phenomenon
in
Einstein
1909b
(Doc. 56),
pp.
189-190, and
had just summarized his views in his
Salzburg
lecture
earlier
in the
same
session in which Ha-
senöhrl
spoke
(see
Einstein 1909c
[Doc. 60],
pp.
496-497).
[3]
The
printed
version
of Hasenöhrl's
text
concludes with the sentence:
"According
to
Einstein's
hypothesis,
the effect established here
would be
just
canceled
by
the
irregularities
of
the
radiation"
("Nach
Herrn
Einsteins
Hy-
pothese
würde
der
hier
statuierte
Effekt durch
die
Unregelmäßigkeiten
der
Strahlung
gerade
aufgehoben")
(Hasenöhrl
1909a,
p.
830).