ABSTRACT
If the heating effect of radium B were 5 per cent. of that contributed by C, the discrepancy between theory and experiment would be quite marked. The heating effect of the emanation was shown to decay exponentially with the same period as its activity, while the heating effect of the active deposit after removal of the emanation was found to decrease very approximately at the same rate as its activity measured by the α rays. A sufficient quantity of radium emanation was available to produce comparatively large heating effects. The variation of the heating effect of the emanation-tube after removal of the emanation was then calculated from the known periods of transformation of radium A, B, and C, assuming that the emanation provided 29 per cent. The γ-ray effect of the emanation-tube at a definite time was compared in terms of the Rutherford-Boltwood standard by the electroscopic method.
