98 LIMITS OF YORKSHIRE AND DERBYSHIRE COALFIELD. [May 1 89 5, 



11. On the Eastern Limits of the Yorkshire and Derbyshire or 

 Midland Coalfield. By»W. S. Gresley, Esq., F.G.S. (Read 

 December 19th, 1894.) 



[Abstract.] 



The Author attempts to throw light on the question of the 

 easterly extension of the Yorkshire, Derbyshire, and Nottingham- 

 shire coalfield beneath the newer rocks. He notices the general 

 trend of the strata, the sizes of other British coalfields, the question 

 of the origin of mountains, stratigraphical considerations, and the 

 faults of the North of England. His object is rather to suggest what 

 he believes to be novel ways of treating the subject than of reaching 

 conclusions or locating limits. 



The Author calls attention to the previously established fact that 

 an anticlinal exists in the Secondary rocks near the southern end 

 of the Lincolnshire Wolds. The existence of this anticlinal has been 

 demonstrated by Mr. A. J. Jukes-Browne (Quart. Journ. Geol. Soc. 

 vol. xlix. 1893, p. 467). Following the reasoning of M. Marcel 

 Bertrand, he infers that an anticlinal in the Carboniferous rocks 

 probably underlies this, and that the easterly termination of pro- 

 ductive Coal Measures under Lincolnshire may be formed by this 

 anticlinal. 



Discussion. 



Prof. Hull stated that at one time he had considered it probable 

 that the Yorkshire and Derbyshire Coalfield was only the western 

 section of a basin, the eastern section of which was concealed under 

 Mesozoic beds. This was the view which he had advocated in a paper 

 read some years ago before the Institution of Civil Engineers. But 

 the results of the deep boring made at Scarle, near Lincoln, had some- 

 what altered his views on this point, as the cores of earthy limestone 

 and breccia and chocolate-coloured clays, brought up from a depth 

 of about 2000 feet, appeared to be referable to the Upper Coal 

 Measures, so fully represented at Ardwick near Manchester, rather 

 than to the Lower Carboniferous series. It was very desirable, 

 however, that the matter should be further investigated by means 

 of fresh borings. 



Mr. Maer wished to direct the Author's attention to a paper by 

 Prof. Arnold Lupton on the Geology of the West Yorkshire Coalfield 

 (Trans. Led. Inst. Mining Engineers, vol. vii. pt. i. 1894, p. 137). 



12. On some Phases of the Structure and Peculiarities of the Iron 

 Ores of the Lake Superior Region. By W. S. Gresley, Esq., 

 E.G.S. (Read December 19th, 1894.) 



[Abstract.] 



The Author has been studying heaps of ore brought from the 

 region lying south-west of Lake Superior since 1890. He describes 

 certain structural features of the ore-fragments, and discusses the 

 evidences of mechanical movements and chemical alteration exhibited 

 by these fragments. 



