A NEW WORLD?

Auckland Star, Volume LXX, Issue 190, 14 August 1939, Page 5

A NEW WORLD?

STRANGE PERILS.

TWO RARE SUBSTANCES.

PROBLEMS CONFRONTING SCIENTISTS. (By a Special Correspondent.) NEW YORK. A strange new world seemed to he dawning over the rain-drenched campus of the Catholic University of America a few days ago as world-famous

physicists, gathered in argumentative groups in the hallways, 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.

The two substances are carbon _ 13 and uranium 235 —tho rare actinouranium which hitherto has only messed up the calculations of geologists trying to determine the age of the earth.

A way was suggested—and just as energetically disputed—of getting both of them in a relatively pure form by means of a device reported from Germany less than a year ago antj greatly improved by Department of Agriculture chemists. '

The potentialities of this uranium 2351 became known to most physicists only last week, when it was revealed that it is the substance whose atoms take part in the atom-splitting phenomenon, first reported two months ago, which generates the greatest energies ever known on earth. It is found in natural uranium, the parent substance of radium, only in a 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 enemy, the enemy of exploding stars, available to mankind. Base of All Living Things. Carbon 13 is the heavy isotope of that element wlii Ji is the basic substance of all lit i 'j tilings. It enters into most of tiie Liasic actiyiAea of life. The

heavy isotope, which may be expected to be chemically identical with the ordinary carbon, but distinguishable physically, would place in the hands of biologists a tool for studying these elemental life functions whose possible revelations in the fields of bio-chemistrv and medicine can only be imagined. The process of separation described was the thermal diffusion of Isotopes' technique, whose most advanced stage is represented by the work of Drs. Brewer and Bramley, of the United States Department of Agriculture. The element whose isotopes it is desired to separate must be got in the form of a gas. There are many gaseous compounds of carbon —for example, the carbon dioxide expelled in the breath, or the carbon monoxide of automobile exhaust fumes.

The apparatus consists essentially of a hot tube in the centre of a hollow tube which is kept reasonably cool by a water jacket. At the top and bottom are two large glass bulbs. It has been found that, when the centre tube is heated, the lighter isotopes, or the lighter molecules, of a gas, surrounding it and completely filling the apparatus, tend to concentrate 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 similar setups until a gas with a heavy concentration of one substance or the other can l>e obtained. Would Kill Everyone in the Room. Less than two months ago, Dr. Harold D. Urey,» Nobel Prize-winner for his first successful isolation of isotopes eight years ago, was lecturing at Catholic University here. He told of attempting the carbon isotope separation by a liquid distillation method which he has used successfully with various other elements. It was possible, he had determined, to make the separation by using hydrocyanic acid. A whiff 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. Drs. L. Onsager of Yale University and W. H. Furry of Harvard University now insist that, at least in theory, it will be possible to obtain the isotope in highly concentrated form through use in the thermal diffusion apparatus of methane or marsh eras, whose molecule is made up of one atom of carbon and four of hydrogen. The molecules containing the j heavy" isotope, about one in ninety,

would be concentrated in the bottom bulb of the apparatus, they believe. Then the hydrogen could be burned away, leaving the heavy carbon.

Actino-uranium concentration offers a far more difficult problem and has infinitely greater implications. New Age for Good or Evil. In order that the thermal diffusion method can be applied, it will be necessary to get uranium in the form of a gas. The only gaseous compound known is uranium fluoride. It would be extremely poisonous—probably fatal to anybody getting a whiff of it. Nobody ever has. Its molecule is not held together very tightly and it is entirely possible, it waft pointed out bv Dr. Onsager, that the heat of the central tube necessary in the thermal diffusion process simply would separate.the atoms of the two elements without producing any concentrations.

Even if it works, the process will be extremely expensive. Uranium fluoride, said Dr. Onsager, is an extraordinarily corrosive gas. It would quickly eat it<s way through glass. Any thermal diffusion apparatus in which it was used would have to be made of almost pure platinum. Construction of a thermal diffusion machine of the dimensions theoretically necessary would l>e almost prohibitive ill cost. This would not necessarily be a bar if there were any reasonable basis for believing that it would work. As the problem stands, nobody knows whether it would work or not, and the only way to find out would be to try.

Sooner or later, the physicists were agreed, somebody is bound to foot the bfll and somebody will try the experiment —so great are the potentialities, completely eclipsing imagination, of a pure actino-uranium preparation. And when the problems are solved, they all agreed, a new age for good or evil will have come to this earth. N.A.N. A.