472 Reports and Proceedings — 



C. E. Be Bance, F.G.S. — Note on Sections exhibiting Variations of 



Thickness in the Middle Coal -Measures of West Lancashire. 

 6r. A. Lehour, F.G.S. — On the Changes affecting the Southern Ex- 

 tension of the Lowest Carboniferous Rocks. 

 Dr. F. Roemer. — On the Mountain Limestone on the West Coast of 



Sumatra. 

 Dr. Von Lasaulx. — On some New Minerals and on Doubly-refracting 



Garnets. 

 Professor F. W. Budler, F.G.S. — On the Tidal Retardation Argument 



for the Age of the World. 

 John Young, F.G.S. — Siliceous Sponges from the Carboniferous 



Limestone. 

 Dr. James Bryce, F.G.S. — On the Granite of Strath Errick and 



Loch Ness. 

 Dr. Bobert Slimon. — On the Upper Silurian Rocks of Lesmahagow. 

 J. E. Taylor, F.G.S. — On the Age, Fauna, and Mode of Occurrence 



of the Phosphorite Deposits of the South of France (Lot, Dept. 



Tarn et Garonne). 

 Professor E. Hull, M.A., F.R.S. — On a Deep Boring for Coal at 



Scarle, Lincolnshire. 

 B. L. Jack, F.G.S.-^On the Tertiary Basalt Dykes in Scotland. 

 W. A. Traill. — On certain Pre-Carboniferous and Metamorphosed 



Trap-dykes and associated rocks in North Mayo. 

 G. A. Lehour, F. G.S. — Report on the Thermal Conductivity of Rocks. 

 Benry Willett, F.G.S.— Od. the Results of the Sub-Wealden (Sussex) 



Explorations. 

 Major Beaumont, B.E., M.P. — On the Sub-Wealden Boring. 

 Dr. GilcJirist. — On the Red Soil of India. 

 G. W. Peach, A.L.S. — On the Circinate Vernation of Sphenopteris, 



and on the occurrence of Staphylopteris in the Carboniferous 



Rocks of Scotland. 



IL — Geological Society of London. — June 21st, 1876. — Prof. 

 P. Martin Duncan, M.B., F.R.S., President, in the Chair. 

 (Concluded from the September Number, p. 427.) 



17. " On Chesil Beach, Dorsetshire, and Cahore Shingle Beach, Co. 

 Wexford." By G. H. Kinahan, Esq., M.R.I.A., etc. Communicated 

 by Prof. Ramsay, F.R.S., V.P.G.S. 



The author carefully compares the situations, structures, etc., of 

 these two shingle beaches, and points out that their wonderful 

 similarity is due to nearly the same natural causes in each case, but 

 that at Chesil the driftage is due to the flow-tide current aug- 

 mented by waves caused by the prevailing winds, while at Cahore 

 the driftage is solely due to the flow-tide currents, its effects being 

 modified by adverse wind-waves. The sorting of the pebbles on 

 Chesil Beach is probably chiefly caused by the progressive increase 

 in the velocity of the tidal current as it approaches the nodal or hinge- 

 line of the tide in the English Channel. The author considers that 

 the current due to the flow of the tide has greater drifting powers 

 than wind- waves. 



