NEW CONCEPTION OF THE ATOM

Southland Times, Issue 25746, 9 August 1945, Page 4

NEW CONCEPTION OF THE ATOM

SOURCE OF ENORMOUS ENERGY An explanation of the modern idea of the atom was given' yesterday by Dr G. H. Uttley, M.A., D.Sc., rector of the Southland Boys’ High School. “Even in Ancient Greece philosophers who pondered deeply on the constitution of the universe guessed that a material substance like wood, or gold was not uniformly filled with matter,” said Dr Uttley. “To them every object consisted of an aggregate of minute particles, or atoms, with empty space between them. The English chemist, Dalton, over, a century ago gave a definite meaning to this idea in his famous atomic theory. He showed that the material universe was made up of atoms, which in different substances differed in weight. Almost until the end of the nineteenth century the atom was considered to be a stable, inconceivably small particle of matter, and, as its name implies, quite indivisible. “Later, the discovery of X-rays, radioactivity and the electron furnished important information on the structure of the atom and led to an entirely new conception of its constitution. Far from being a structureless, hard, impenetrable entity, the atom was shown to have an open structure with a central electrically-charged nucleus about which electrically-charged particles, the electrons, revolved in orbits similarly to the revolution of the planets round the sun. SPLITTING THE ATOM “Experiment had shown that the atoms of the heavier radioactive elements like uranium and radium were spontaneously disintegrating into other elements with an accompanying outpouring of energy and a re-arrange-ment of the planetary atomic systems. Rutherford, the great New Zealand scientist, first caused the disintegration of the nuclei in the lighter elements, and his experiments ushered in a new epoch in physical science, for he brought about for the first time the artificial transformation of one element into another, as distinguished from the spontaneous transformation of _ the radioactive elements. He had split the atom.

“The energy produced if all the atoms of a substance could be split would be enormous—many times that of the most powerful chemical explosive known—but in the past the number of atoms that have been split has been so small that the energy released has been practically useless. We know that enormous energy would be released if the hydrogen nuclei could be made to combine with the electrons from helium nuclei. It is estimated that if about one-seventh of an ounce of helium could be built up from hydrogen, there would be a release of energy from the nucleus equivalent to about 1,000,000 horsepower for one hour, but it would have to be released in such a form that we would be able to make use of it practically.

“Recent work has shown that a selfsustaining disintegration of uranium may' be possible. Such a process would have tremendous significance, as the energy set free in one pound of uranium oxide amounts to the enormous total of approximately 8,000,000 kilowatt hours. The few experiments made up to 1940 had not supported the idea of a self-supporting process. It is possible, however, that some such process may lie behind the successful production of the latest bomb to be used in this war. The Allied scientists have in some way found it possible to release some of the vast storehouse of energy held fast in the atom and make it obedient to their will.”