PROCEEDINGS 
OF THE 
W 4 
ROYAL SOCIETY OF EDINBURGH. 
SESSION 1909-10. 
Part VI] YOL. XXX. [Pp. 439-518. 
CONTENTS. 
NO. PAGE 
XXIX. Equilibrium in the Ternary System : Water, Potassium 
carbonate, Potassium ethyl di-propyl-malonate. By 
J. W. M‘David, B.Sc., Carnegie Research Scholar. 
( Communicated by Professor James Walker), . 440 
{Issued separately July 14, 1910.) 
XXX. On a New Method for differentiating between Overlapping 
Orders when mapping Grating Spectra. By Alexander 
D. Ross, M.A., B.Sc., Assistant to the Professor of Natural 
Philosophy in the University of Glasgow, . . 448 
{Issued separately July 28, 1910.) 
XXXI. On Two Relations in Magnetism. By R. A. Houstoun, 
M.A., D.Sc., Ph.D., Lecturer in Physical Optics in the 
University of Glasgow. {Communicated by Professor 
A. Gray, F.R.S.), . . . . . .457 
{Issued separately July 28, 1910.) 
[ Continued on page iv of Cover . 
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