Transcription: The broad features of the Constitution of all atoms are now well established. As a result of the splendid work of Bohr and those who have followed him, we are able to understand the arrangement and the motions of the planetary electrons and the way in which light or X-rays are emitted when the atom is disturbed. Unfortunately, we have much less information about the Constitution of the minute, central nucleus. We know the value of the charge on each nucleus and also its mass, but we have no precise information of the nature and arrangement of the particles composing it.
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