TRANSACTIONS OF SECTION B. 525 
the alkali metals.!_ Cesium chloride was exposed to radium rays for half an hour 
at 16° C.; the radium compound was then removed and the temperature of the 
cesium salt was raised to 37° C. The phosphorescence was now markedly 
increased by the rise of temperature. May we not, then, suppose that the bodies 
occluded in radium compounds have radio-activity conferred on them while there, 
and that this radio-activity is increased by the heat which is necessary for their 
expulsion ? 
Crucial tests of the validity of this energy-transformation theory appear to be 
presented in the following additional facts. If water be admitted to the contents 
of a radium bromide tube its phosphorescence is practically undiminished.” 
Rutherford has studied the matter quantitatively, and finds that solution of a 
solid radium compound to a thousand times its volume does not appreciably affect 
its radio-activity, which he has attempted to explain on the atomic disintegration 
theory.? I have, however, pointed out that under such conditions there is approxi- 
mate constancy of absorption of external radiant energy which ought to result ina 
like constancy of radio-activity.* 
Again, the 60 per cent. difference of heat emission in the Curie-Laborde and 
Curie-Dewar estimations appears to receive a rational explanation from this point 
of view. At normal temperature the output of heat from a radium compound was 
found to be of the order of 100 calories per gram of radium per hour, while at the 
temperature of boiling oxygen it was only 38 calories. Now a colour-changing 
substance, whilst passing from normal temperature towards the region of absolute 
zero, becomes white, or, in other words, lessens its capability of absorbing external 
radiant energy; and it is now suggested that probably to this cause is to be 
attributed the low numbers obtained by Professors Curie and Sir J. Dewar at the 
temperature of boiling oxygen. 
10. Pseudomorphosis in Organic Persulphates. 
Sy Professor R. WoLFFENSTEIN. 
1l. A New Theory of the Periodic Law. 
Ly Professor G. J. Stokes, M.A. 
Many mathematical and physical interpretations of the Periodic Law have been 
suggested. That of the author, based on a logical analysis due to De Morgan, 
offers itself as more than an illustration—as a method by which chemical facts may 
be deductively re-discovered. 
It has been shown by De Morgan that between any two things x and y there 
are only a definite number of logical relations possible. If we take the diagrams 
by which these are represented and arrange the elements under them, it is shown 
that a number of qualitative facts in chemistry may be deductively arrived at. 
TUESDAY, AUGUST 23. 
The following Papers were read :— 
1. On the Velocity of Osmosis and on Solubility : a Contribution to the 
Theory of Narcosis. By Professor I. TRAvuBE. 
Upon the results of a series of investigations, by plasmolytic methods, of the 
velocity of the osmosis of chemical compounds into the protoplast, Overton bases 
the theory that the magnitude of the distribution coefficient between such sub- 
stances as fat, cholesterins, and lecithins on the one hand, and water on the other, 
! Journ. Chem. Soc. 1904, 85, 816. 2 Chem. News, 1903, 88, 206. 
3 Nature, 1904, 69, 222. 4 Tbid., 1904, 69, 295. 
