In part I the various methods of determining the energy distributions of electrons are described. Reasons are given for the choice of a semi-circular focusing spectrograph. The construction of the magnet, the spectrograph box, the field measuring devices and the coincidence Geiger-Muller counters are given in considerable detail.
In part II the experimental energy distributions of the C, N¹³, Na²², P³² and Ra E nuclear electrons are described. In addition the distribution of the internally converted electrons from the Th Pb 2.62 mev gamma ray and of the secondary electrons from the gamma rays of N¹³ and Na²² are given. The connection between these gamma rays and the complexity of the Beta spectra is discussed. In those cases where an independant estimate of the energy of the radio-active transformation is available there seems to be a discrepancy between this independent estimate and the experimental value for the end point of the continuous beta spectra. Several possible explanations of the discrepancies are discussed.
In the appendix the calculations of the distribution of the interally converted electrons from the Th Pb gamma ray are given.