Reports and Proceedings — Geological Society of London, 139 



regions the ice increases in thickness mostly from the top, by the 

 freezing of the overflowing water ; but in other regions of light 

 snowfall it increases mostly from the bottom. Throughout the winter 

 the ice remains firmly frozen to the shore, except that it falls with the 

 lowering of water in the lakes. In the spring it thaws along the 

 shore, and around any stones. Loose ice floating on the water is then 

 pushed against the shore by wind, and sand and stones are thrust up 

 by and in front of it, often to the back of the beach, and there piled 

 into rough and heavy walls or ramparts. 



3. Beekite. — An article on this form of orbicular chalcedony is 

 contributed by Mr. "W. H. Wickes (Proc. Bristol Nat. Soc, 1910). 

 Named after Henry Beeke, Dean of Bristol (born in 1751 and died in 

 1837), who first called attention to the mineral, the original describer 

 appears to be unknown. After dealing as far as possible with 

 references to the same mineral substance, dating back to 1751, 

 Mr. Wickes gives a list of formations and fossils shoAving how widely 

 distributed are the incrustations of Beekite, from an Orthoceras in the 

 Cambrian Limestone of Durness to the Norwich Crag. It occurs 

 only on marine calcareous organisms, and in the opinion of the 

 author the material has been deposited from silica in solution in sea- 

 water, in and around cavities produced in the shells and other organic 

 structures by boring animals. 



4. Catalogue of Photogkaphs of Geological Subjects, prepared 

 by the Geological Survey and Museum. 8vo ; pp. 62. Price 6d. 

 Edinburgh, 1910. — This work, issued as a memoir of the Geological 

 Survey of Scotland, supplements that relating to England and Wales, 

 which was noticed in the Geological Magazine for July, 1910, p. 330. 

 The Scottish Survey has been longer engaged in the taking of 

 photographs of geological interest, and the number now catalogued 

 amounts to 676 whole-plate and 1,237 half-plate subjects, as against 

 a total of 800 in the English collection. Among the Scottish subjects, 

 of which brief descriptions are given in the Catalogue, are many 

 features in the Lewisian gneiss, Torridonian, and Cambrian (including 

 great thrusts), Ordovician, Carboniferous, Triassic, and Jurassic. The 

 igneous rocks of Skye, Arran, Argyll, and Ayr are well illustrated ; 

 likewise glacial phenomena, landslips, screes, faults, arches, caves 

 and various forms of weathering, peat-mosses, etc. Negatives, prints, 

 lantern-slides, and bromide enlargements of any of these photographs 

 can be obtained at a fixed tariff, on application to the Director, 

 Geological Survey, either at 33 George Square, Edinburgh, or at 

 28 Jermyn Street, London. 



EEPOETS -A-HSTID ZFIROOEEZDIHSTGi-S- 



I. — Geological Society of London. 

 1. January 25, 1911.— Professor W. W. Watts, ScD., M.Sc, F.R.S., 

 President, in the Chair. 

 The following communication was read : — 



"The Skomer Volcanic Series (Pembrokeshire)." By Herbert 

 Henry Thomas, M.A., B.Sc, E.G.S. 



•■- This series of volcanic rocks is developed in the west of Pembroke- 

 shire, and takes its name from the island of Skomer, where the 



