DOC.
99
MAY
1908 71
the
idea of
having
mercury
be driven
by
centrifugal
force into
a
trough
that
is
fastened
to the
inner
perimeter
of
a
wheel,
and
of
having
a
small
wheel,
which has
approximately
the
same
radial
velocity
as
the
Hg, dip
into the latter,
so
that
the little
wheel makes
contact with
the
Hg,
and
if the little wheel
is
appropriately
toothed,
then the
contact will
be
broken and reestablished
again,
then
I will make
only
one
drawing. (By
no means
let
this sentence convince
you
that
I
can
make
even more damnably
convoluted
sentences
than
a
patent
office.)
It
just
seems
to
me
rather
difficult to
protect
the idea that
consists
simply
in
re-fixing
the
Hg
in
the
process
of rotation.
Next
Sunday
I will send
you
the
drawing along
with
the
description.
I also discussed with
Conrad the
same
idea
as
that
for the circuit
breaker but
applied to
brushes
in
fast-running
dynamos.[4]
Laval?[5]
Closely
related
to it
is
the
regulator
at
rest
roughly hyperbolic
Hg
Hg
in
motion
The
Hg
rises
high along
the
walls and the
pin goes
out
The
contact is
interrupted
In
this
way
one
can
regulate
the number
of
revolutions of
a
motor
very precisely
because
the
thing
is sensitive.
To
be
sure,
I
consider these
last two
things
to be
technically unimportant,
but
they
show
the
difficulties involved in
a
precise
formulation.
I
promised
you
that
I would draw
my
idea
for
pneumatic tires,
so:
wood
wood
steel-band spring
steel-band spring
pins that prevent
the wooden pegs
from falling out
cast-steel
rib&.
leather