Evening star., 1938-04-25

sion here.
and watch what happened. Prof
Einstein thought of a way Of doing it,
however, using as clocks the newly
discovered canal rays"
Canal rays. first reported by the
German physicist Stark in 1906. ap-
pear as streams Of heavy, positively
charged particles Of atomic propor-
tionS.
They are bi-product Of the pro-
duction OF X-rayS When stream
OF electrons from negatively charged
electrode are hot against a target
some Of them penetrate deep into the
interior of the targets atoms knock
ing other electrons loose from the
inner shells. These dislodged cleo
irons. as they find places for them
selves In other atomic orbits, cause
emission Of energy from the atoms.
This energy is x-radiation.
Constitute Back Explosion.
Some Of the electron bullets, how
ever, go deeper into the planetary
system Of the atom and set free
positively charged protons. These
are attracted backwards at enormous
speeds towards the negative electrode.
They constitute back explosion Of
the atomic bombardment
When splits are cut in the electrode
the positively charged streams go right
through them and can be caught on
the other side. They are known as
canal rays" because Of their pas
sage through these Sits, or canals" "
All the time the negatively charged
electrode is sending out electrons in all
directions and some OF these combine
with the positively charged particles.
When this happens light is emitted
known as RECONCILIATION lumines-
cense" This light is characteristic OF
the element which Is reformed and
can be split into its wave lengths by a
spectroscope placed behind the elec-
trode.
DR., Ives then turns to the Doppler
effect. known for nearly 100 years
Every element. when it is made
luminescent, sends out light with a
distinctly Characteristic spectrum made
up of wave-lengths emitted by no
other element. Because of this
chemists are able to detect almost in
f1nitesimably minute amounts of any
particular element in a combination
for If one of the characteristic wave
lengths appear in the spectrum it is
indisputable evidence that the element
is present in the source Of light.
Spectrum Lines Shifted.
But if the source Of light is moving
these spectrum wave-length lines are
shifted slightly to the right or left
toward the red or violet ends of the
spectrum. II it is moving toward the
spectroscope the shift is in the violet
direction, and If it is moving away
the shift is toward the red. The de-
gree of the displacement in either
direction is proportional to the speed
of the source of light. BY this means
astronomers can tell the direction and
speed of movement Of stars millions Of
light years distant in space. This IS
the Doppler effect.
Now the spectrum of the "recombi-
nation luminescense" coming from
atoms moving at enormous speeds also
shows the Doppler effect but in the
past this has been practically impossi-
BILE to measure because of the various
speeds at which the particles are
moving. These measurements were
made possible by new canal ray tube
recently perfected by Prof. A. J.
Dempster of the University of Chi
cago.
In DR.. Ives experiment each canal
ray particle constitutes a moving clock.
It's speed and direction are measured
by the shift in the spectrum of the
light 1t emits, just as the rate Of q
clock is determined by the position
OF its hands on the dial. Knowing
the speed of the moving particles and
their direction, the amount Of this
shift can be calculated. With the
new apparatus DR.. Ives was able to
find this predicted shift. an extremely
minute one, within the limits Of ex-
perimental error He measured very
accurately the shift Of one wave-
length-the blue line of hydrogen
gas which is standard in spectrum
measurement because 1t is 50 promi-
nent.
His apparatus could be oriented so
that the direction of the particles
would travel in the direction of the
motion of the earth or at any angle
to it and their luminescense reflected
back to the spectroscope. In effect he
might be considered as bouncing rubber
balls Of time from the top of mov-
ing train-the earth. He found that
the spectrum shift remained precisely
the same regardless Of the direction of
the back-bounce.
Thus his experiment turns out the
same as did the Michelson-M Morley ex-
pertinent with light beamS and more
over into the fantastic contraction
hypothesis. thus verifying Einstein's
30-year-old prediction. The atom
watches actually slow down with speed.
"Pf