The Washington times. [volume] (Washington [D.C.]) 1902-1939, 1924-11-28
made
To ROAR LIKE
NIAGARA
Tiniest Particle Known to
Science HoWIs in Vacuum
Tube Amplifier
BY IntsrpatiOnal News serviua.

/.
BY InternationaI News servlsa.
ANN ARBOR, Mich, Nov. %. -
Experiments by which scientists
have been ableN to listen to the
movement of eleetrons, the small.
est particles of all matter, were
described here today by Doctor A.
w. Hull, OF the research laboratory
CT the General Electric Company,
at the annual meeting OF the Amer.
lean Physical Society.
The vacuunn-tube amplifier, in
which the amplification is carried
to a hundred thousandfold, and
with which millionfold can be
reached, makes this possible, Doc
tro Hull stated. The sound pro-
duced by the electrons Is caused by
bombardment of the plate by cleo
irons released from the hot fila
ment. It is these eleotrons which
carry the current and which make
the operation Of the tube possible.
The noise is, therefore, a funda-
mental property of electron ennis
sion, a characteristic of the cleo.
iron, according to Doctor Hull.
The experiments have been con-
Quoted jointly by Doctor Hull and
Doctor H. HI. Williams, of the Uni
versity Of Michigan, at the uni
versity.
Proves Up Theory.
The noise, due to the electrical
oscillation which is set up by the
impacts Of the Individual electrons
on the plate, is known as the
Schrot effect and was predicated
on theoretical grounds by Doctor
Schottkyp Of Berlin. The energy
OF each blow is extremely minute,
but, like raindrops, the energies OF
the many individual impacts add
and their sum becomes very large.
With sufficient amplification, Doc.
tor Hull stated, the blows may pro.
duce roar like that of Niagara.
To listen to the sound of the
electron Is a feat in itself which
gives added charm to the vacuum
tube. Listening to the electruu
however, is but incidental to the
studies which have been made by
the scientists.
The electron is the unit charge
of electricity, and the determine.
ton of its value is Of the utmost
importance. The oil.drop method.
devised by Professor Millikan, in
the physics laboratory Of the
University of Chicago, gave science
its first accurate measurements of
the charge of the electron. Ac-
curate as the experiments are,
however, it is desirable that they
be checked by some independent
method.
Method Of Measuring
Millikan's method of measuring
the charge of an Aelectron is based
on the influnce of gravity and OF
electric charges on minute oil
/ 'droplets." These droplets are SO
small that the effect of gravity
causes them to fall only a quarter
or an inch in ten seconds-they
are baout three-hundred-thou
OF an inch in diameter and are
observed in a powerful beam OF
light with a small telescope. They
are then seen as specks of lighi
against a dark background.
| I'M the formation Of these small
drops with an atomizer, occasion
ally one becomes charged by fric
ton !. O., 1t may carry an additions
electron. If, then, the droplet i.
between two electrically charged
plates it will behave differently
from the unchanged particles
Doctor Hull stated. Those which
are not charged will fall. The
charged particles will be attractet
to the positive plate. BY the use
of the proper voltage between the
plates, these charged particles car
be made to fall more slowly, hell
stationary, or caused to move IN
ward. If two electrons instead o.
one, are held by the droplet, thu
effect is doubled. Measurement.
made by this method give the
value of the electronic charge very
exactly. In recognition of the i'm
portance of this work, the Nobe
prize in science for last year wa.
awarded to Professor Millikan.
Newly Discovered.
Doctors Hull and Williams have
measured the charge of the cleo
iron, in different way, by means
OF the Schrot effect, and have
opened a field for research which
promises to add to the knowledge
regarding the electron and it.
properties.
1t was not such long time age
that the electron was unknown
First, scientists had the molecule
itself so small that mans ability
ever to see even one Of the larg
est may seriously be doubted
Then came the atom, the minute
integral part Of the molecule. Fol
long time the atom was consid
cred as the ultimate particle Of
matter. But each element pre-
sents a different atom. Science
was not content to rest. It sought
to connect all phenomena, and the
electron was the result.
1t was discovered that all matter
Is composed of electrons, the diff
ferent substances resulting from
the different properties possessed
Dy the atoms, according to the
number and arrangement of the
electrons they contain.