On the velocity of the cathode particles emitted by various metals under the influence of Röntgen rays, and its bearing on the theory of atomic disintegration

The numerous theoretical and experimental investigations during the past few years of J. J. Thomson, Rutherford, Becquerel, and others on the radio-active substances have demonstrated conclusively that the only theory which can satisfactorily account for the phenomena observed is that of atomic disintegration, a process which is apparently going on in several, if not in all, of the elements. This process, however, seems to be entirely spontaneous, to depend only on the special substance under investigation, and to be outside the control of any external influence brought to bear upon it. Immense labour has been expended on experiments involving the utmost variation in the temperature and in the chemical and physical conditions of the elements, but all to no purpose so far as influencing the rate of atomic disintegration is concerned. As far as is known at present, no variation in the output of energy has been detected. There are, it is true, results by Curie and Danne, and more recently by Makower, which seem to show an effect of temperature on radium emanation. These results are not, however, confirmed by Bronson in his experiments on the same subject, so that no definite conclusion can yet be reached on this point. Obviously, it would be of immense interest and importance, not only from the scientific point of view, but also from the technical and commercial standpoint, if some method could be devised of stimulating or retarding at will this output of atomic energy. That there is a great store of energy in the atom seems now beyond question, and if this reservoir could only become available, all our present conditions might be completely revolutionised. Naturally, the only mode of attacking this problem is by investigating what the nature of this atomic emission of energy is.