CONTENTS. 
PAGE 
Election of Office-Bearers, . . . . , .1 
Introductory Address by the President, the Right Hon. Lord 
Moncreiff, . . . . . . .2 
On the Structure of Euplectella. By Dr F. E. Schiiltze. Communi- 
cated by Sir Wyville Thomson, . . . . .2 
On Equidifferent Multiples of Irrational Quantities. By Mr E. 
Sang, . . . . . . . .2 
Algebra of Relationship. Part II. By A. Macfarlane, M.A., D.Sc., 
F.R.S.E., ........ 5 
On Dust, Fogs, and Clouds. By Mr John Aitken, . . .14 
Solar Eclipse, 31st December 1880. By Mr E. Sang, . . 18 
On the Preparation of Adamantine Carbon or Diamond. By R. 
Sydney Marsden, D.Sc., F.R.S.E., F. Inst. Chem., &c., . . 20 
Note on an Electric Sonometer. By Professor James Blyth, . 28 
Theory to account for certain movements exhibited by low forms of 
Animal Life, and termed Amoeboid. By John B. Hay craft, Senior 
Demonstrator of Physiology in the University of Edinburgh, . 29 
On the Effect of Permanent Elongation on the Specific Resistance 
of Wires. By Mr T. Gray. Communicated by Sir William 
Thomson, . . . . . . . .31 
Meconic Acid. By Mr D. B. Dott. Communicated by Professor 
Crum Brown, . . . . . . .31 
On the Crystallisation of Silica from Fused Metals. By R. Sydney 
Marsden, D.Sc., F.R.S.E., F. Inst. Chem., &c., . . .34 
On Phosphorus Betaines. By Professor E. A. Letts, . . 37 
On the Action of Haloid Compounds of Hydrocarbon Radicals on 
Phosphide of Sodium and on the Salts of Tetra-Benzyl-Phos- 
phonium. By Professor Letts and N. Collie, Esq., . .46 
Notice of an Easy Method for determining the Position of the 
Principal Focus of an Object-Glass. By Mr Edward Sang, . 50 
Note on the Temperature Changes due to Compression. By Prof. 
