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six miles north of Manchester, of five fossil trees in a position vertical 
to the plane of the strata in which they stand. ‘The roots are im- 
bedded in a soft argillaceous shale immediately under a thin bed 
of coal. Near the base of one tree, and beneath the coal, more than 
a bushel of hard clay nodules was found, each inclosing a cone of 
Lepidostrobus variabitlis. The bark of the trees was converted to 
coal, from one quarter to three quarters of an inch thick; the sub- 
stance which has replaced the interior of the trees is shale; the cir- 
cumference of the largest of them is 154 feet at the base, 74 at. the 
top, and its height 11 feet. One tree has spreading roots, four feet 
in circumference, solid and strong. By the care of Mr. Hawkshaw 
these trees have been preserved, and a covering is erected over 
them. ‘The attendant phenomena seem to show that they grew 
upon the strata that lie immediately beneath their roots. 
Mr. Barber Beaumont, in a communication respecting these same 
trees, considers that no drifted plants occur in coal fields, and that 
all the vegetables which are now converted into coal, grew upon 
swampy islands covered with luxuriant vegetation, which accu- 
mulated in the manner of peat bogs; that these islands, having 
sunk beneath the sea, were there covered with sand, clay and shells, 
till they again became dry land, and that this operation was repeated 
in the formation of each bed of coal. In denying altogether the pre- 
sence of drifted plants, the opinion of the author seems erroneous ; 
universal negative propositions are in all cases dangerous, and more 
especially so in geology: that some of the trees which are found erect 
in the coal formation have not been drifted, is, I think, esta- 
blished on sufficient evidence; but there is equal evidence to show 
that other trees, and leaves innumerable which pervade the strata 
that alternate with the coal, have been removed by water to con- 
siderable distances from the spots on which they grew. Proofs are 
daily increasing in favour of both opinions: viz. that some of the 
vegetables which formed our beds of coal grew on the identical 
banks of sand and silt and mud, which being now indurated to 
stone and shale, form the strata that accompany the coal; whilst 
other portions of these plants have been drifted, to various distances, 
from the swamps, savannahs, and forests that gave them birth, par- 
ticularly those that are dispersed through the sandstones, or mixed 
with fishes in the shale beds. 
