542 Geological Society: Anniversary Address, 1843. 
logists may well be led to suppose that the theory which, if I may so 
speak, has recently been rendered fashionable, of the origin of coal 
by subsidence of vegetable matter im situ, must be considered esta- 
blished as of general application. I, however, adhere to the cau- 
tionary remarks which I ventured to make last year, and will now 
endeavour to impress upon your minds the inapplicability of such 
a theory, however true under limitations, to large portions of the 
carboniferous strata in different parts of the world. 
Since our last Anniversary statements have appeared in our own 
country, both supporting and impugning the probable truth of 
the theory. The last meeting of the British Association being held 
at Manchester, geologists were there assembled in the centre of a 
tract appealed to with great reason by the supporters of this theory 
as containing many proofs of its truth; for, in the immediate vici- 
nity of that town there occur, as you all know, the beautiful examples 
of vertical stems of large trees apparently in their original position, 
which were formerly described before this Society. After giving an 
elaborate and satisfactory account of the great Lancashire coal-field, 
showing that its lowest members, formed on the flanks of the Penine 
chain, and subordinate to the millstone grit, contain marine shells 
analogous to those of the Mountain Limestone series, and stating 
that they are surmounted by a middle and an upper group, the former 
constituting the richest coal-field, Mr. Binney describes in great 
detail the composition and contents of all the numerous roofs and 
floors, as well as also of the coal-seams, which are included between 
them. He shows also that the roofs vary in their nature at different 
places, even over the same seam, and contain the remains of many 
vegetables, sometimes, as near Manchester, in vertical positions, 
Sigillarie being in such cases a most abundant plant; other 
roofs of black shale in the lower field are loaded with 
Pectens, Goniatites, Posidonia, and fishes. The coal-floors, on 
the contrary, present a much greater uniformity of structure, 
fireclay similar to the underclay of Mr. Logan being most 
abundant; though it is admitted, that a different or siliceous clay also 
frequently occurs, and that two instances are known where the coal 
rests at once on coarse quartzose sandstone. Seeing, that with one 
exception, all the floors throughout an estimated thickness of near 
5000 feet contain the plant Stigmaria ficoides usually with its leaves 
attached,—that both the roofs and floors indicate a very tranquil me- 
thod of accumulation,—that the coal is free from admixture of foreign 
or drifted materials, and that large trees frequently stand upright, 
this author is induced to believe that the vegetables out of which 
the coal has been formed, grew upon the spot. 
At the same meeting this view was contested by Mr. W.C, William- 
son, also well acquainted with the structure of the country around 
Manchester. His chief arguments were, however, derived from other 
tracts, and they assisted in proving,—Ist, the frequent association 
of marine shells with coal (as at Coalbrook Dale, and in Yorkshire); 
2ndly, the very triturated and broken condition of the plants, as 
well as their great intermixture in the sandstone and grits, coupled 
