THE ATOM RECENT DISCOVERIES

Evening Star, Issue 22327, 1 May 1936, Page 7

THE ATOM

RECENT DISCOVERIES

ROWER TO EXPLODE IT. Professor Niels Bohr recently gave a brilliant account of recent discoveries concerning the structure of atoms to the University College' Chemical and Physical Society, states the ‘ Alanchester Guardian.’ He explained the new theory of the atomic nucleus which has largely been inspired by the recent experiments with neutrons. This theory gives the suggestion that atoms may be made to explode if struck by particles of very high energy. The provocation of the explosion of matter is one of the ideas which Air H. G. Wells and other speculative writers have used in forecasts of the outcome of scientific discovery. Professor Rohr said he 'thought particles with an energy of perhaps one thousand million volts might be sufficient to provoke the explosion of an atom. Present scientific apparatus produce particles with an energy of one to ten.million volts, and the multiplication of this power a hundred or a thousand fold is not beyond distant hope. Particles or rays with an energy of a thousand million volts have already been detected among the cosmic rays that impinge upon the earth from outer space, and it is possible that the showers or bursts ot particles which have been observed in connection with cosmic rays may be a result of atomic explosions caused by the extra swift cosmic particles. ONE BILLION TONS. The nucleus of an atom is made of extremely dense matter. If a lump ot such matter the size of a human fist could be obtained it would weigh about a billion tons. In fact, the whole of the British fleet of ships would not be able to carry more than a hundredthousandth part ot such a lump. The extremely high density of the nucleus of atoms illustrates one of the differences between an atom as a whole and its nucleus. The atom is very spacious, while the nucleus is extremely compact. It is not surprising that the laws governing the structure and behaviour of atomic nuclei are proving to be quite different from those governing whole atoms or familiar matter. The roominess of the atom allows its widelyseparated constituents to move with much independence. Thus the mechanics of whole atoms is comparatively simple. hi the nucleus the constituent particles are close together and react in a more connected manner. Professor Bohr compared them with a group of billiard balls lying on a circular table with low cushions. If an external ball is shot into the group it starts a series of mutual collisions which cause the impinging ball to be captured. If the balls go on colliding one hall may presently collect enough energy to jump over the cushion. It appears that this game of intro-nuclear snooker explains why the nuclei or atoms of iron capture neutrons fired into them. The extraordinary nature of the new tacts concerning neutrons is illustrated by the behaviour of cadmium. It has been shown that the nuclei ot atoms of this metal arc able to catcli neutrons at a distance a hundred times the size'of a nuclei.