Evening star. [volume] (Washington, D.C.) 1854-1972, 1926-08-20
RAYS PENETRATE
WHERE X-RAYS ARE POWERLESS
Recently Discovered Force Is to Be Described
9 as Feature in Annual Report From
Smithsonian institution

An account Of the powerful pene.
trating rays newly discovered by
Millikan will be included in the next
Smithsonian annual report. on the
compilation of which the institu-
ton is now engaged. These new rays
are invisible. but, like X-rays. can
penetrate metals A thin sheet of
lead, however, as everybody knows.
will stop N-rays. Milkan's rays will
travel through a layer of lead six feet
thick.
1t seems that all space is alive with
these new rays. They do not origi-
nate on the earth, but come in to us
with the velocity of light from the
great universe beyond the atmoS-
phnre Probably they are formed in
the breaking up of the atoms which
compose the stars.
No one can yet foresee by what re-
markahle uses they may come to
serve MS When Faraday demon
strated before the Royal Societey that
all that was necessary to obtain an
electric current was to move a wire
across the pole of a magnet. a woman
in the audience asked him of what
use the experiment was. That dis
covery formed the basis Of all
modern electrical machinery. Fara-
day replied Madam, will You tell me
of what use is Il newborn babe?
Faraday's babe has grown up into a
giant now. SO it may prove with
Millikans.
NichoiG Closed Gap.
The extraordinary penetrating
power of the new rays depends on
the extreme shortness of their wave
length Ordinary broadcasting radio,
or HertZian rays, have waves from
100 to 5000 meters. Langley years ago
found rays in the suns and moons
Deems, quite invisible to the eye, Of
a wave length of hundredth of a
mllimeter. German scientists later
found that rays ten times longer than
I.angley'S are sent out by special
lamps. and they extended the radio
region all the way from the usual
wave length down to as short as one
centimeter, or 1000 times Langley's
longest. The late Prof. Nichols, who
died so tragically on the day the
National Academy of Sciences Build
ing was dedicated at Washington,
closed up the gap entirely between
the longest lamp rays and the short
est radio rays.
Light. such as we see with, con-
sists of rays between the lengths
0 .0O04 and 00007 mllimeters. and sun
RAYS contain all varieties of rays from
00003 to COLA millimeters in wave
length Shorter sun rays than 0.0O03
cannot reach us because in the high
atmosphere longer sun rays than
0.014 millimeterS are cut off by the
water vapor which pervades the cir.
Air, indeed even when freed from
tlaca 10 n Sfil1
shorter rays than 0.0003 millimeters.
Yet by using vacuum apparatus
Schumann, Lyman. Mllikan and
others have traced the lamp spectrum
back to 0.0000-millimeter waves and
beyond. After this we come directly
into the domain Of X-rays used in
hospital practice. They run to 100
times shorter still. or about 5000 times
shorter than yellow light. The new
rays which Millikan has found are
1000 times shorter in their wave
length than the average X-rays. What
a gamut from these to radio? Yet all
are alike in being just waves and differ
only in wave length. Some few affect
us as light, but most are wholly in
visible. We may call them the OBJ
scure cousins of light.
All In 50 Years.
All Of these discoveries in the ex-
tension of the spectrum have occurred
within the last SO years. Each Of
them as it came along got into the
Smithsonian annual report of its year.
The report is a chronicle .of the i'm
portant advances of science. 1t in
cludes summary of the institution S
work for each year and a number Of
articles selected on the basis of their
capacity to inform the layman of the
experts new conquest of nature. Such
great discoveries as the fact that mos
.auitoes spread yellow fever. as Dubois
finding in Java of the manlike fossil,
Pithecanthropus erectus; as Rontgen's
stumbling on X-rays, as Thomson's
proof that the tiny atoms contain