PROCEEDINGS OF GEOLOGICAL SOCIETIES. 
261 
Mr. Cnnnington exhibited a beautifully-finislied flint celt or adze, nine 
and a half inches long by three wide at the edge, which had been found, 
with others, during the present year, at Crudwell, near Malmesbury. 
A letter was read from Profe->sor Buckman, accompanied by a geological 
section, announcing the discovery in Cirencester of a patch of Corubrash, 
proving that, as its environs consist of Forest marble and Great Oolite, the 
town itself is situated in a valley of depression. A letter of thanks from the 
Geological Society for the contribution to its library of the Proceedings" 
of the Club was then read, as was also an invitation to meet the Malvern 
Club at Dudley, on the 18th of June, from the newly-established Severn 
Valley Naturalists' Field Club, whose head-quarters are at Bridgnorth. 
The proceedings terminated with a paper by the Jlsv. S. Lysons, on the 
" Names of Places in Gloucestershire." 
Manchester Geological Society. — March 31.9^. — A very important 
Eaper was read by Mr. Joseph Dickinson, the President, " On the Coal- 
trata of Lancashire." 
In the first volume of the Transactions of this Society there are papers 
" On the Geology of Manchester and its Vicinity," and " On the Geology 
of the Lancashire and Cheshire Coal-Fields," by Mr. Binney. These 
papers were given about 2i years ago ; but although so many years have 
elapsed since they were written, Mr. Dickens testified to the accuracy which 
characterizes most of the information the}^ contain. The author's purpose 
in his present paper was to give an account of the whole subject, and, in 
doing so, to " Tell not as new what everybody knows," but, whilst fully ac- 
knowledging former authorities, to supply required corrections, together 
with additional matter of his own. 
The base of the Lancashire coal-formation rests upon the mountain lime- 
stone, which is seen cropping out near Clitheroe ; within no part of the area 
of the coal-field, however, are the lower measures so much exposed as to 
exhibit the limestone. It is covered by a very thick deposit of shales and 
grit, the thickness of which has never yet been correctly ascertained, but 
probably thicker than at any other part in England. 
At the boundary between Lancashire and Cheshire the lowest workable 
coal-seams crop out at Mossley, near Staley bridge ; they then skirt round 
near the eastern boundary of Lancashire, passing at certain places into 
Yorkshire (where sometimes, without having cropped out, they dip away 
again in the opposite direction, and become overlaid by the whole of the 
Yorkshire coal-field), through to Littleboro'; thence midway between 
Bacup and Todmorden, passing near the Portsmouth station on the railway 
between Todmorden and Burnley ; then gradually curving a little to the 
west, including the Worsthorn quarries, and so on nearly to Colne ; thence 
turning in a westerly and south-westerly direction, along Padiham Heights, 
through Simondstone and Bead, where the crop becomes very steep, dip- 
ping almost at an angle of 45*^; then, leaving Blackburn outside, they pass 
through Oswaldtwistle to Eccleshill, Over Darwen, across to Chorley, 
round by Welsh Whittle, Heskin, and thence to Latham Park and Blague- 
gate ; then southward, keeping a little to the west of St. Helens. On the 
south side the coal strata are overlaid by the Red Eock, or New Red Sand- 
stone, Permian, etc. 
The line thus given forms nearly half a basin, and throughout the entire 
length the general inclination of the strata is inwards to a centre, — the 
inclination or dip being very much varied by the difierent faults with 
which the basin is divided, from nearly level to an angle of 45°. 
The coal-measures included in this Lancashire field have been divided 
into three series, namely, — the lower, or Gannister, the middle, and the 
