S76 



SCIENCE-GOSSIP. 



GEOLOGY 



-^7 





conducted by edward a. martin, f.g.s. 



Geology of the Isle of Portland and 

 Weymouth. — A Memoir of the Geological Survey, 

 dealing with the Isle of Portland and Weymouth, 

 has been published. Mr. A. Strahan is the 

 author, and the work is issued at ten shillings 

 and sixpence. 



Othniel Charles Marsh. — The eminent 

 American geologist, Othniel Charles Marsh, Pro- 

 fessor of Palaeontology at the University of Yale, 

 died on the 18th March. He was M.A. of Yale, 

 Hon. Ph.D. of Heidelberg and LL.D. of Harvard 

 University, an F.G.S. of London and first recipi- 

 ent, in 1877, of the Bigsby Medal. He was awarded 

 the Cuvier Prize in 1887 by the Institute of France 

 in honour of his restorations of extinct reptiles, 

 birds and mammals. In 1879 Dr. Marsh delivered 

 a remarkable address on " The History and Method 

 of Palaeontological Research," whilst President of 

 the American Association for the Advancement of 

 Science. In 1882 he was appointed Director of 

 Palaeontology to the U.S. Geological Survey, and 

 a year later Curator of the Vertebrate Fossil Col- 

 lection in the National Museum at Washington. 



Pocks of the Essex Drift. — When the Rev. 

 A. W. Rowe collected and examined the rocks and 

 boulders scattered around the village of Felstead, 

 near Braintree, in Essex, he found a most remark- 

 able and varied amount of material to choose 

 from. Felstead stands on high ground over- 

 looking the River Chelmer. Within a radius of 

 four miles of the village he found stones and 

 boulders of the following rock species : granite, 

 syenite, quartz - porphyrite, quartz - tourmaline, 

 felsite, quartz - trachytes, felspar - porphyrites, 

 trachytes, and dolerite. In the quartz-tourma- 

 lines, which seemed very abundant, the ground 

 mass was granitic, and contained schorl in abun- 

 dance. It sometimes occurred as needles in other 

 crystals, or in aggregates in other grains ; some- 

 times in spheroidal patches, or in appearance of 

 thin threads. 



Schorl Rock in the Drift. — The distribution 

 of this rock over the south of England was dealt 

 with in a paper before the Geological Society, on 

 February 1st, by Mr. A. E. Salter, F.G.S. 

 Specimens which he collected were referred to 

 Professor Bonney, who identified the parent rocks 

 as the felspathic grits of the south-west of 

 England. The most westerly point at which the 

 pebbles have been detected is on Great and Little 

 Haldon Hills, eight hundred feet above O.D., 

 where they are of larger size, more abundant, 

 and coarser-grained than elsewhere. Thence they 

 are traced to the north and south sides of the 

 Thames Basin, and into East Angiia at Walton- 

 on-the-Naze, Aldeburgh, &c. There is a general 

 decrease in height in the deposit in which the 

 pebbles occur in passing from west to east, and 

 the pebbles appear to have taken two main 



courses — one along a peneplain west to east from 

 Dartmoor, the other from south-west to north- 

 east across England. The pebbles are absent 

 from the Wealden and Bagshot areas, from the 

 Hampshire Basin and its bounding hills, and from 

 the highest and presumably oldest gravels north 

 of the Thames. 



Barton Clay Fossils. — Fossils from the 

 Barton Clay of Hampshire have always had a 

 great fascination for the geologist collector 

 because of their beautiful state of preservation. 

 We have received a box of thirty different species 

 from Mr. R. Charles, the veteran who, in his 

 seventy-second year, still finds enjoyment and 

 healthy employment in collecting the fossils 

 which he is now offering our readers. His prices 

 are so extremely moderate that one cannot under- 

 stand how it can be worth his while, excepting as 

 a labour of love, and the endeavour to diffuse a 

 knowledge of these representatives of Upper 

 Eocene times. Mr. Charles has received testi- 

 monials from University College, Bangor ; Owens 

 College, Manchester ; Royal College of Science, 

 South Kensington, &c. No collection of specimens 

 is complete without one of these series, now that 

 they are brought within reach of the youngest 

 collector. 



Brighton Cliff Formation. — Owing to fresh 

 falls in the cliffs to the east of Brighton, the face 

 presents for a quarter of a mile, a new section of 

 the Brighton cliff formation. No less than ten 

 feet of well-rounded gravel and boulders now rest 

 horizontally upon a low cliff of chalk which rises 

 from the present beach to about ten feet. The 

 largest boulders of flint are in the base of the 

 raised beach, and the change downward is an 

 abrupt one into chalk in situ. There is now no 

 sand between the two, and there is no layer of 

 green-coated flints at the junction. The gravel 

 just rests on a platform of chalk. As one reaches 

 the eastern boundary of the formation, the beach 

 instead of being continuous from top to bottom, 

 splits up into a top and oottoni layer of about a 

 foot thick each ; whilst the space between them is 

 tilled with " reconstructed chalk " in which the 

 boulders increase in size easterly, until the whole 

 presents an appearance of chalk, almost as 

 originally laid down, with the usual joints and 

 cracks. The lower part of the Elephant bed, 

 which rests upon the topmost gravel, becomes 

 more chalky in an easterly direction, and is made 

 up of rounded fragments of chalk, together with 

 larger boulders of the same. Owing to the manner 

 of the falls, the cliff has been cut back more in 

 some parts than in others, with the result that 

 the lines of stratification, which are everywhere 

 most distinct, appear to dip at a high angle 

 towards the sea. It is just possible that these 

 lines may be due to current-bedding; in which 

 case it would seem to follow that much of the 

 upper portions of the Elephant bed are missing, 

 having been planed away with the upper part of 

 chalk at its rear. Great masses of red sandstone, 

 grey sandstone, and here and there a mass of 

 tertiary iron-red breccia, strew the feet of the 

 cliffs. In the raised beach I excavated from just 

 above the chalk two rounded boulders of granite, 

 and a few rounded laminae of green Woolwich 

 sandstone. Probably 99 per cent, of the stones 

 were flints, with little or no sand in the interstices. 

 — Edward A. Martin. 



