TRANSACTIONS OF SECTION C. 623 



angular blocks of limestone fallen from the roof firmly imbedded in it. This layer 

 was eight feet deep, as far as we saw it. The last two feet are laminated and 

 contain smaller blocks. At the depth of about twelve feet from the surface we 

 came to part of the solid limestone tlooror side of the cave, sloping steeply down- 

 wards. There were no indications of a change in the nature of the deposit at the 

 junction with the limestone, and the clay appears to extend much deeper than the 

 level at present reached. Thus below the stalagmite purely mechanical deposits 

 succeed, and no limestone blocks are found above this horizon, although the stalag- 

 mite has been removed over a large part of the floor of the chamber. No traces of 

 a fauna have been as yet found below the first hardish stalagmite ; indeed all the 

 deposits passed through below the stalagmite indicate the former presence of a 

 still lake in which the great thickness of clay slowly accumulated. Further work 

 was stopped by the heavy rain which flooded the shaft dug in the clay. It is in- 

 teresting to note that the former condition of Chamber II. is identical with the 

 present state of the third chamber in the preponderance of mechanical over 

 chemical deposits. The change from mechanical to chemical deposits was pro- 

 bably produced by a change from accumulation in still water to accumulation 

 in running water. Possibly also the absence of blocks fallen from the roof in the 

 stalagmite may be due to the bicarbonate of lime contained in the water, which 

 percolated through the roof, cementing together the limestone blocks. The absence 

 of this cement when the clay was deposited may be due to the absence of solvent 

 power in the water which then percolated through the roof. For no carbon 

 dioxide would be evolved from a soil deficient in organic matter — as the soil cover- 

 ing the Yorkshire hills for a period long after the Glacial period must have been. 

 I wish to express my best thanks to J. R. Tennant, Esq., of Kildwick Hall, Leeds, 

 and to J. R. Eddy, Esq., of Carleton, Skipton, on behalf of the Duke of Devonshire, 

 for their kind permission to work the cave, and especially for the kind help and 

 advice that Mr. Eddy has given all through the work. I also wish to heartily 

 thank those gentlemen who have helped me in the work itself. 



MONDAY, SEPTEMBER 5. 

 The following Reports and Papers were read : — 



1. Seventh Report on the Circulation of the TTndenjroimd Waters in the 

 Jurassic, New Red Sandstone, and Permian Formations of England, and 

 the Quality and Quantify of the Water supplied to towns and districts 

 from these formations. — See Reports, p. 309. 



Third Report on the Tertiary Flora of the North of Ireland. — See 



Reports, p. 1-52. 



3. On the Formation of Coal. By Edward "Wethered, F.G.8., F.C.S. 



The author first reviewed the researches of Hutten, Goeppert, MacCulloch, 

 Sir James Hall, Sir W. Logan, and Dr. Dawson, and then summed up the con- 

 clusions now entertained as to the formation of coal, as follows : — 



First, That the beds of fireclay which underlie all seams of coal, represent the 

 original land-surfaces upon whicli the coal-forming vegetation grew. 2nd. That 

 the Stigmaria found in the underclays were the roots of that vegetation, which 

 implies that the plants were of the Lepidodendroid order. 3rd. That the vegeta- 

 tion grew near the mouths of great rivers, in swampy ground, and there under- 

 Avent submergence ; changes then took place which converted the vegetable matter 



