SCIENCE-GOSSIP. 



3i9 



GEOLOGY 



gJlk: 



^^^?^Mra^ 



CONDUCTED BY EDWARD A. MARTIN, F.G.S. 



A London Gravel Section.— A gravel section 

 in London Wall, in the City of London, has been 

 laid bare prior to building operations, by the de- 

 molition of a large number of warehouses. Beneath 

 some eight feet of made ground was found about 

 ten feet of dark carbonaceous clay containing 

 freshwater shells — such as Planorlns, Cyclas, etc., 

 and numerous traces of vivianite. Lower is a thin 

 bed of broken bones, these resting on gravel to a 

 thickness of about ten feet, below which a shaft 

 had been sunk for some distance in London Clay. 

 The layer of bones, which seem to have been 

 deliberately broken out of all recognition, was 

 extremely puzzling. To whatever cause they are 

 to be attributed, they were laid there before the 

 water flowed in, in which the clay was afterwards 

 deposited. We have here, in fact, a natural deposit 

 resting upon an artificial one. Stowe says that in 

 Moorfields there were numerous brickfields, the 

 brick-earth being excavated for brick-making. 

 The water then accumulated in the low-lying spots 

 which were thus made, these afterwards being 

 favourite skating-grounds. We can scarcely think 

 that the clay could have been formed in the com- 

 paratively short period since Stowe's time. I 

 regard the layer of bones as of older date. There 

 must have been some reason for the breaking of 

 the bones. Perhaps the layer here exposed may 

 represent the floor of Eoman wild-beast dens, in 

 which case there would have been ample time to 

 allow of the deposition of the clay. Opinions on 

 this interesting section would be valuable. — E. A. 

 Martin. 



Indurated Chalk. — In reference to Mr. E. 

 R. Sawer's remarks, ante, p. 201, about the induration 

 of chalk, may I point out that beds of indurated 

 chalk occur at Corfe, in Dorsetshire ? The rock is 

 so hard that it is used for mending the roads in 

 some parts of the neighbourhood. The cavities 

 which occur in this chalk contain crystals of calcite, 

 and the same mineral may be found as veins 

 traversing the mass. This is not a case of " con- 

 tact-nietamorphism." The alteration in the cha- 

 racter of the rock was probably induced during the 

 uplifting of the beds through heat generated by 

 pressure. If water were present, hyclrothermal 

 action may have produced some changes ; but I do 

 not remember that there was sufficient visible 

 evidence in support of the hydrothermal theory to 

 the exclusion of others. — Ccoil Cams-Wilson. 



Geological Society of London.— At the 

 annual meeting, held on February 15th, Mr. J. J. H, 

 Teall was re-elected president, and Messrs. J. E. 

 Man, H. W. Monckton, Professor H. G. Seeley, 

 and W. Whitaker vice-presidents of the Society. 

 Messrs. R. S. Herries and Professor W. W. Watts 

 remain as secretaries, and Mr. W. T. Blandford as 

 treasurer. The report of the Council showed a 

 total fellowship of 1,334 at the end of 1900. The 

 Wollaston Medal was awarded to Professor Charles 



Barrois, the Murchison Medal to Mr. A. J. Jukes- 

 Browne, the Lyell Medal to Dr. R. H. Traquair, 

 and the Bigsby Medal to Mr. G. W. Lamplughl 



Director-General of Geological Survey.— 

 It is with considerable regret one hears of the 

 forthcoming retirement on March 1st of Sir 

 Archibald Geikie from the Director-Generalship 

 of the Geological Survey. It is forty-six years 

 since Sir Archibald's first official connection with 

 the Survey, and he is still in the possession of a 

 valuable store of energy and enthusiasm. We arc 

 not, therefore, surprised to hear that he has a1 

 present no intention of laying aside his unofficial 

 work, and we trust he will continue to wield both 

 pen and hammer for many years to come. Those 

 who have heard him speak or lecture must have 

 been struck by the originality of his descriptions, 

 and by the intelligible manner in w T hich he has 

 placed his facts and opinions before the audience. 

 It is intended, as mentioned in Science-Gossip 

 last month, to entertain Sir Archibald early in 

 March at a complimentary dinner. 



Insect Wing from Carboniferous Rocks. — 

 Owing to the rarity with which insect remains 

 have been found in our carboniferous rocks, special 

 interest attaches to a short article in the " Geo- 

 logical Magazine," by Mr. H. A. Allen, describing 

 portion of a wing, with a neuration apparently 

 differing from any hitherto obtained. This has 

 come to light from the top of the four-foot seam 

 in the Lower Coal Measures of Llanbradach Col- 

 liery, Cardiff. The specimen was obtained by Mr. 

 G. Robbings, and has been provisionally placed in 

 the genus Fouquea, as F. cambr crisis. 



Deep Colliery Shaft. — A shaft is shortly to 

 be sunk to a depth of 1,850 feet at Lyktrens in 

 Pennsylvania, and from the bottom of the shaft 

 a tunnel will be driven 1,200 feet long, in order 

 to reach the anthracite seam. At present the 

 deepest shaft in that region is at Wadesville, which 

 is 1,600 feet deep. 



Uintacrinus in Chalk. — The remarkable free- 

 swimming crinoid, Uintacrinus, discovered twenty- 

 five years ago in the Niobrara chalk of Kansas, and 

 almost at the same time in the Lower Senonian of 

 Westphalia, promises, after all, to be one of the 

 commonest crinoidal forms in the Marsupites zone 

 of our own English chalk. Uintacrinus is a stalk- 

 less crinoid. A complete morphological description 

 of U. socialis will be found in the " Proceedings of 

 the Zoological Society for 1893 " (pages 974-1001). 

 by Dr. F. A. Bather. Since this description was 

 written Mr. Bather has explored the cliffs east of 

 Margate with complete success, and he finds that. 

 next to columnals of Boii/rgxieticrinus, cup-plates 

 and brachials of UintaeHnus are the most common 

 fossils. Other parts of Kent besides Margate have 

 produced similar evidence. Mr. C Griffith has 

 found similar plates at Grately. near Andover. 

 The Recklinghausen glauconiferous sandstone has 

 been also searched by Dr. Bather, and he rinds 

 that the genus is as plentiful there as at Margate. 



Charnwood Forest. — The Quarterly Report 

 of the Leicester Literary and Philosophical Society 

 for October 1900 contains in the geological section 

 three interesting photographs of Charnwood Forest. 

 showing a quarry between High Sharpley and 

 Cademan. a band of grit in the Blackbrook series. 

 and the Hanging Rocks, Woodhouse Eaves. The 

 paper is by Professor W. W. Watts. M.A., F.G.S. 



