156 Geological Society : — 



all stones in the Drift of north-western England are derived from 

 the basins of the Irish Sea, and of rivers draining to it, except some 

 stray fragments that may have come from the Highlands of 

 Scotland. 



4. " Eipple-marks in Drift." By T. Mellard Reade, Esq., C.E., 

 F.G.S. 



Amongst published notices of drift-deposits the author has never 

 met with any description of ripple-marks, though, if the drift was 

 formed under water, some should be found. In a spot to which his 

 attention was called by Dr. Callaway, the Old Park Eield sand-hole 

 at Ketley, near Wellington, Salop, in a stratified drift-deposit, he 

 had found early in 1883 three distinct beds of ripple-marked 

 laminae . One of the ripple-marks in the highest bed measured 

 9 inches from crest to crest and 1J inch in height, and had been 

 produced by a wind from the N.W. 



In July 1883 the author found ripple-marking in hard, fine loamy 

 brown sand underlying a compact mass of Boulder-clay at Tranmere, 

 Cheshire, in one of the approaches to the Mersey Tunnel. The 

 marks were on a sloping bank, and the sand was faulted in places 

 with a throw of from 2 to 4 inches. In the sand shell-fragments 

 occurred, some of them being recognizable as those of Turritella 

 terehra, Cardium edule, Tellina balthica, and a Pholas. 



The position of this section in a hollow between higher ground was 

 favourable to the preservation of ripple-markings. The beds un- 

 doubtedly are those named by the author the Low-Level Boulder- 

 Clays and Sands. 



March 5.— Prof. T. G. Bonney, D.Sc, E.R.S., President, 

 in the Chair. 



The following communications were read : — 



1. " On the Structure and Formation of Coal." By E. Wethered, 

 Esq., E.G.S., E.C.S. 



The author, having referred to the work of previous investigators, 

 pointed out that seams of coal do not always occur in one bed, but 

 are divided by distinct partings, some of which, as in the case of 

 the Durham main seam, contain Stigmarice. It was important to 

 notice this feature for several reasons, but especially as the beds of 

 coal, defined by the partings, showed differences both in quality and 

 structure. In the case of the shallow seam of Cannock Chase they 

 had at the top a bed of coal 1 foot 10 inches thick, the brown layers 

 of which were made up of macrospores and microspores. The 

 bright layers were of similar construction, except that wood-tissue 

 sometimes appeared ; also a brown structureless material, which the 

 author looked upon as bitumen. He, however, objected to that 

 term, and thought that hydrocarbon aceous substance would be 

 preferable. What this hydrocarbonaceous material originated from 

 was a question for investigation. In the lower bed of the Welsh 



