438 ae ee. TRANSACTIONS OF SECTION B. 
with the formula of the compound. It would, therefore, appear a priori that 
success is likely to be realised in cases where the inter-metallic compound does 
not form solid solutions with either of its constituents. The magnesium-zinc 
alloys constitute a system of this kind; these two metals form the well-defined 
compound MgZn,. The author has shown’ that this compound can be prepared 
by distilling alloys containing an excess of zinc beyond that required for the 
compound MgZn,, the excess of zinc volatilising and the alloy of minimum 
vapour pressure consisting of the compound. It has further been shown that, 
under suitable conditions, this compound can be distilled without decomposition. 
Attempts have been made to investigate the volatilisation of mixtures in which 
the compounds can form solid solutions with their constituents. Although no 
general conclusions have yet been reached, the following results have been 
obtained :— 
(1) Copper and cadmium are quantitatively separable by volatilisation of the 
cadmium. 
(2) Magnesium and cadmium yielded a non-homogeneous distillate. 
3. Report on Diffusion in Solids. 
By C. H. Descu, D.Sc., Ph.D.—See Reports, p. 348. 
4. Sorption of Hydrogen by Palladium. By Dr. A. Hour. 
5. The Causes of the Induction Period in the Interaction of Hydrogen 
and Chlorine. By R. pz J. F. Srruruers. 
6. The Chemical Nature of Uranium X, Radio-Actinium, and 
Thorium B. By AvExanDER FuEcx, B.Sc. 
Marckwald and Keetman’s statement that thorium and uranium 2 could not 
be separated was submitted to as thorough a chemical examination as possible. 
The chief method employed in the attempted separation of these two bodies 
was fractional precipitation, but in no case was it found possible to alter the 
concentration of the short-lived radio-element in thorium. 
Similarly radio-actinium and thorium and thorium B and lead were found to 
be two pairs of chemically inseparable elements. 
7. Report on Solubility. By Dr. J. Varcas Eyre. 
See Appendix II., p. 795. 
PRIDAY, SEPTEMBER 6. 
Joint Mecting with Section K. 
The following Papers and Report were read :— 
1. (a) The Enzymes of Linum. (b) Variation in the Flax Plant with 
Locality. By Dr. J. Varcas Eyre. 
2. Variation in Lotus corniculatus. 
By Professor H. E. Armsrrona, F’.R.S. 
3. The Biochemistry of Flower Pigmentation. 
By Professor F. Krrsie and Dr. E. F. Armstrona. 
* Roy. Soc. Proc., A., vol. 86, 1911, p. 67. 
