Evening star., 1940-04-13
Of Sturs, Men
And Atoms
Notebook Of Science Progress
In Field, Laboratory
And Study
By Thomas r. Henry.

More than 40 elements hitherto un-
known in the universe have been created
during the past few months by bonn
harding uranium, the heaviest of the
building stones Of creation, with slow
neutrons.
This entirely unexpected development
from the phenomenon discovered under
dramatic circumstances barely q year
ago, in which the uranium atom is split
in two with the production of energies
which before had existed only in the
interiors Of the stars, was revealed to
the Washington branch of the American
Chemical Society the other night by DR..
Philip Abelson Of the Carnegie Institu-
ton OF Washington.
When uranium splitting was first re-
ported and verified in the United States
in February 1899, 1t was hailed as the
first tapping Of atomic energy-the in
credibly tremendous binding power Of
creation. Atoms were split in two with
the release of approximately zoe, 0,0o0, 900
volts energy. 1t soon was found, how
ever, that extreme diflculties stood in
the way of producing this power for
practical purposes. The new develop
ment has come largely as by-product
of the efforts to overcome these hurdles
1t was thought at first that uranium
split in only one way, into roughly
approximate halves. One-half was iden-
titled as the element barium and the
other appeared to be the very rare ele-
ment maSurium, Of which there were
only few grams in the world.
The present results show that the
split may come in great number of
ways, depending on the way the atom is
hit. This is matter of pure chance and
cannot be controlled in any way Chem
ical analyses of what is left after the
bombardment of pure uranium show
traces OF the elements bromine, krypton,
rubidium, strontium, yttrium chromium,
columbium, molybdenum, masurium, tin,
antimony, tellurium, iodine, xenon,
caesium, barium, lanthanum and cerium
These are present in the bombardment
residues in amounts barely detachable by
the most delicate chemical means-in
some cases less than 100 trillionths of a
gram. But, DR.. Abelson explained, these
elements in the forms hitherto known
are only the end products. They change
into each other in series of explosive
steps lasting from few seconds to two
months-and each step is an hitherto
unknown element. The process is much
the same as that by which uranium it
self changes into a particular form of
lead in nature-producing in the process
such intermediate elements as radium.
All OF the chips of uranium when they
are first split off. he explained, are ra-
dlo-active. AS an example, he cited the
metallic element tellurium in one of the
explosive forms in which it has been
found IN the residue. 1t changes into
an exploding iodine This in turn
changes into an exploding form of the
heavy gas xenon. The xenon turns into
radioactive calcium. This explodes into
barium, In a form which is not radio.
active and which will remain unchanged
forever. Thus four new elements make
their appearance in this single reaction.
"A few OF the new elements which have
been identified, DR.. Abelson said, are
Identical with some artificial radiums"
which already have been produced in
the laboratory by bombarding various
elements with deuterons, the atoms of
heavy hydrogen. The majority, how
ever. were hitherto unknown and appar.
emily can be produced in no other way.
The work, DR.. Abelson explained, is only
IN its beginning and there is no reason
TO suppose that many more new ele-
ments may not be found-some, for ex-
ample, with life periods of more than
two months
The possible uses OF the new-found
elements still are obscure but some al
ready promise to be of value in tracing
the progress of various food constituents
through the body and others NAV be
found which will be indispensable in
medical treatments. The discovery of
these exploding substances has attracted
little notice up to the present because it
has proceeded step by step in various
places-but chiefly at the physical labo-
ratory OF the University of California
with which DR.. Abelson was associated
before joining the Carnegie staff. It has
been mostly under the direction of DR.
E. o. Lawrence, inventor of the cyclo-
tron atom-s smashing machine.
Up to the present, DR.. Abelson points
out. all the uranium splits have been
into relatively heavy elements. The
heaviest element continues to explode
very roughly in halves. There has been
no splitting off Of exploding light chips
such as radioactive carbon or oxygen
Thus, he said, all the new products NAV
be expected to fall about in the middle
OF the table of elements where are found
some OF the rarest of all the building
stones of nature.
In spite of the extremely small
amounts produced, DR.. Abelson ex.
planned, the uranium fissure technioue
with the extremely small expenditure of
power which is required, promises to be
a much cheaper means of manufactur.
ing some Of the artificial radiums" than
any other process found to date.
keystone Aut0 Cluh