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THE GASES OF THE ATMOSPHERE

more complete works by Professor Rutherford, Mr. Frederick Soddy, and the Honourable R. J. Strutt, if he wishes to learn more about the nature of the disintegration of the parents of these gases, radium and thorium, and the astonishing changes which they spontaneously undergo. The beginning of the twentieth century has been characterised by a revolution in chemical thought more wonderful than any which has ever been seen, and this has had its influence on our conception of the nature of the atmosphere. But the ground has only been surveyed ; future years will certainly bring fuller knowledge.

May 1905.