For almost 2,500 years, man was wrong. From the time of Socrates, he had thought of atoms as the smallest particles of matter. In the last century, scientists discovered still tinier particles within atoms.
Some particles, negatively charged, are 2,000 times as small as the lightest-known atom. Scientists named these specks electrons, learned that every atom also contained a positively-charged nucleus; and that the force holding the nucleus together is the world’s greatest potential source of power.
The day this energy could be put to work for man would be the first day of the atomic age. This week, it seemed the atomic age might not be far away.
Bombs bursting in air
Ten years ago an atomic particle known as a neutron was discovered. Neutrons (they have no electrical charge) are produced everywhere and constantly by the bursting of atoms by cosmic rays.
A neutron has immense energy and more penetrating power than other atomic particles. It can split atomic nuclei. On passing through water, it slows down, loses energy, yet becomes better than ever for blowing up atoms.
When uranium (a metal abundant in Canada, Czechoslovakia, Colorado and elsewhere) is bombarded with slow neutrons an unusual splitting occurs. Neutrons passed through water split certain atoms squarely in two. The metal has two kinds of atoms. differing in weight. Alfred O. Nier of the University of Minnesota isolated enough for a test. Columbia University’s physicists made the test, announced findings this week.
Only the lightweight atoms, of mass 235, were splitting. Therefore, the physicists theorized, if you put a chunk of U-235 in water, you should get immediate results: A neutron let loose by cosmic rays would break up atoms of the U-235, set off a chain reaction like the burning of coal. This reaction would set free (1) 200,000,000 electronic volts of energy to make the water boil, provide steam for practical power; (2) neutrons to repeat the process indefinitely and thereby achieve the nearest thing yet to perpetual motion.
If this can be made to work on a large scale, atomic power is a fact.
What it means
Experiments indicate that one pound of lightweight uranium would be equivalent in power output to 3,000,000 pounds of gasoline or 2,500 tons of coal. Five to 10 pounds would drive a battleship around the seas for 100 years.
One step remains: Isolation of light uranium in fairly large quantities. Researchers are working on that one at Columbia and Minnesota universities, in General Electric laboratories, in Nazi Germany.