222 BROWNIAN MOTION
to his friends Conrad and Paul Habicht about his
discovery
of
a
method
for the
measure-
ment
of
small
quantities
of
electrical
energy.
Soon
afterward the Habichts tried to build
the device ("Maschinchen")
proposed by Einstein.[114]
At the end
of
1907,
Einstein
dropped
his
idea
of
obtaining
a
patent
for
the
device, "primarily
because of
the
lack of
interest
by
manufacturers"
("hauptsächlich
wegen Interesselosigkeit
der
Fabrikan-
ten").[115]
Instead,
he
published a paper on
the basic features
of
his method
(Einstein
1908a
[Doc.
48]),
a paper
which stimulated further work
on
the device
proposed
by
Ein-
stein.[116]
While
the
use
of
the device for
measuring
fluctuation
phenomena
in conductors
proved
to be
difficult,[117] experimental
work done
by
others
soon provided
evidence
for
the atomistic constitution
of
matter and
electricity
that exceeded
Einstein's
initial
expec-
tations.[118]
[114]
On
16
August
1907,
Einstein wrote
to
Conrad and Paul Habicht:
"I
am
not
a
little
as-
tonished
at
the breakneck
speed
with which
you
have
made the
'Maschinchen'
" ("Ich bin nicht
wenig
erstaunt über
die
rasende
Schnelligkeit
mit
der
Ihr das Maschinchen
gemacht
habt").
[115]
Einstein to Conrad
Habicht,
24 December
1907.
[116] See,
e.g.,
Habicht and Habicht
1910;
for
further discussion,
see
Vol.
5,
the editorial
note,
"Einstein's 'Maschinchen'
for the Measurement
of
Small
Quantities
of
Electricity."
[117]
For further
discussion,
see
note
4
to Ein-
stein 1908a
(Doc.
48),
p.
492.
[118]
For Einstein's
expectations,
see
Einstein
to Jean
Perrin,
11
November
1909,
quoted
ear-
lier in
this section. For
a
discussion
of
experi-
mental
studies
of
the
atomistic constitution
of
electricity by
Millikan and
others, see
Holton
1978.