Evening star., 1939-05-01
By THOMAS r. HENRY.


campus of the Catholic University
of America last week as world
famous physicists, gathered IN ar
gumentative groups in the Railways,
discussed possibilities of obtaining
two substances-one of which might
pave a road to longer life and the
other a road perhaps to infinite
power and perhaps to death.
It was the closing day of the an
nual spring meeting OF the Amerl-
can Physical Society.
The two substances are carbon Is
and uranium 235-the rare actlno-
uranium which hitherto has only
messed up the calculations of geolo-
gists trying to determine the age OF
the earth.
A way was suggested-and just
as energetically disputed-of getting
both of them in relatively pure
form by means of device reported
from Germany less than a year ago
and greatly improved by Depart
ment of Agriculture chemists.
Potentialities Just Revealed.
The potentialities of this uranium
235 only became known to most
physicists yesterday, when it was
revealed that 1t is the substance
whose atoms take part in the atom
splitting phenomenon, first reported
here two months ago, which gen.
crates the greatest energies ever
known on earth. 1t Is found in nat
ural uranium, the parent substance
of radium, only in ratio OF one
part to 1000 A relatively pure
preparation of it must be obtained
In order to take the first steps IN
making the fabulous atomic energy,
the energy of exploding stars, avail
able to mankind.
Carbon 13 is the heavy isotope
of that element which is the basic
substance of all living things. 1t
enters into most of the basic activ1-
ties of life. The heavy isotope,
which may be expected to be chem
ically identical with the ordinary
carbon but distinguishable physlc-
ally, would place in the hands OF
biologists a tool for studying these
elemental life functions whose pos
sible revelations in the fields of bio
chemistry and medicine can only
be imagined.
The process of separation de-
ecribed was the thermal diffusion
of isotopes technique, whose most
advanced stage is represented by
the work of Drs. Brewer and Bram-
lev of the United States Department
of Agriculture. The element whose
isotopes it is desired to separate
must be gotten in the form of
gas. There are many gaseous COM
pounds of carbon-for example, the
carbon dioxide expelled in the
breath or the carbon monoxide OF
automobile exhaust fumes.
Simple Apparatus.
The apparatus consists essentially
of a hot tube in the center OF a
hollow tube, which is kept reason
ably cool by a water jacket. At the
top and bottom are two large glass
bulbs. 1t has been found that when
the center tube is heated the lghter
tsotopes, or the lighter molecules OF
q gas surrounding it and completely
filling the apparatus, tend to con-
centrate in the upper bulb and the
heavy ones in the lower bulb. This
process may be repeated over and
over again by a succession OF SIM
liar setups until gas with heavy
concentration of one substance or
the other can be obtained.
Less than two months ago DR..
Harold D. Urey, Nobel Prize winner
for his first successful isolation OF
tsotopes eight years ago, was talking
in a lecture at Catholic University
here. of attempting the carbon
tsotope separation by liquid dis
tillation method which he has used
successfully with various other ele-
ments. 1t was possible, he had de-
termined, to make the separation
by using hydrocyanic acid. A whif1
of this, getting out of the apparatus
would have killed everybody in the
room.
DR.. Urey Is still doubtful whether
It can be accomplished In any other
way. Today Drs L. Onsager OF Yale
University and w. H. Furry OF Har-
ward University insist that, at least
In theory, it will be possible to OBJ
tain the isotope in highly concen-
trated form through use in the ther-
NAL diffusion apparatus OF methane
or marsh gas, whose molecule Is
made up of one atom of carbon and
four of hydrogen. The molecules
containing the heavy isotope, about
! in 80, would be concentrated In the
bottom bulb of their apparatus, they
believe. Then the hydrogen could
be burned away, leaving the heavy
carbon for biological experiments.
The possibility, they said, depends
on a mathematical factor which has
not been tested in actual experiment.
The experiments would be relatively
safe. Methane smells horribly, but
is not very poisonous, at least In
small whiffs Already, they said, 1t
has been found possible to separate
methane and ammonia, which have
nearly identical weights. Heavy
methane, in fact, would have exactly
the same weight as ammonia and
might be expected to act in the
same way.
More Difficult Problem.
Actino-uranium concentration Of
fers a far more difficult problem
and has infinitely greater implica-
tionS.
In order that the thermal diff
fusion method can be applied it will
New Under-arm