DOCS.
107, 108
JUNE-JULY
1908 77
107.
From Lucien Chavan[1]
Geneva, 23
June
1908
Returning
Wednesday.
Cordial
greetings
L.
Chavan
108.
From
Paul Habicht
Basel, 4
July
1908
Dear
A. E.
I
have
given some
thought
to
the
Maschinchen,
and
I
have also
done
some
calculations. While I
was doing
so, I
got a
new
idea,
which
might
have, perhaps,
a
few
advantages.[1]
The
accompanying
sketch
is
the
cross
section of
a
small
wheel,
into the center
of
which
a
small
tube
opens
from above
(like now),
but
with
the
differ-
ence
that
the
Hg
opening
is
made
as narrow as
a
possible,
since the
Hg
serves
there
merely
as a
sealant.
Assume that, for
some reason
or
other,
the
pressure
in the wheel
=
0,
then the
Hg
will
seek
to enter
the wheel
at
position a
with
a velocity
of
about
2.7
m/sec[2]
let the
peripheral
velocity
be 20
m/sec
then the
relative
motion of the
Hg
is
as
follows
:
u
=
20
m
Thus,
the
triangular
surface
is
now
Hg-free
and
c
=
2,7
ry
/ /
7
1
:
- void
of air
Thus,
the wheel remains
void of
air.
If there
was
air in
the
wheel,
then
it
goes
out at
that
place.
The
point
least
accessible
to
analysis
is
the
exit
of the
air. It
is
obvious
that
it
must
occur periodically.
The
cause
of this
periodicity
may
be
a
fluctuation
phenomenon,
as
for
example
in the
case
of
an
ordinary wheel, which,
from
the
moment
it
gets
filled with
air,
does
not
draw in
new
air
until
a
sufficient
quantity
of
Hg
is present
again,
or
the
cause may
be
an
external
one,
e.g.,
fins This
is
how I
imagine
that
the
apparatus
functions: