ABSTRACT
This chapter analyses the soft type of γ radiation from radium B. Evidence of lines corresponding to the more penetrating rays from radium B and the penetrating rays from radium C has been obtained on the photographs. The stronger lines due to radium B appeared with great distinctness on the photographic plate. Most of the photographs were taken with crystals of rock-salt, the crystal in some cases being a slip less than a millimetre thick, in others a specimen about a centimetre thick. In most of the authors experiments they have employed a crystal of rock-salt, since its structure has been worked out in detail by W. H. and W. L. Bragg, and since it gives fairly strong reflexions for soft radiations. On the general theory of the nucleus atom, the nucleus charge determines the chemical and physical properties of the atom, and it is consequently of great importance to determine the value of this constant for the radioactive atoms.
