would be first
peat, then lignite, and last, it may be, coal, with the stems of
killed trees standing up out of it into the new mud and sand-beds
above it, just as the Sigillariae and other stems stand up in the
coal-beds both of Britain and of Nova Scotia; while over it a fresh
forest would grow up, to suffer the same fate--if the sinking process
went on--as that which had preceded it.

That was a sight not easily to be forgotten. But we need not have
gone so far from home, at least, a few hundred years ago, to see an
exactly similar one. The fens of Norfolk and Cambridgeshire, before
the rivers were embanked, the water pumped off, the forests felled,
and the reed-beds ploughed up, were exactly in the same state. The
vast deposits of peat between Cambridge and the sea, often filled
with timber-trees, either fallen or upright as they grew, and often
mixed with beds of sand or mud, brought down in floods, were formed
in exactly the same way; and if they had remained undrained, then
that slow sinking, which geologists say is going on over the whole
area of the Fens, would have brought them gradually, but surely,
below the sea-level, to be covered up by new forests, and converted
in due time into coal. And future geologists would have found--they
may find yet, if, which God forbid, England should become barbarous
and the trees be thrown out of cultivation--instead of fossil
Lepidodendra and Sigillariae, Calamites and ferns, fossil ashes and
oaks, alders and poplars, bulrushes and reeds. Almost the only
fossil fern would have been that tall and beautiful Lastraea
Thelypteris, once so abundant, now all but destroyed by drainage and
the plough.

We need not, therefore, fancy any extraordinary state of things on
this planet while our English coal was being formed. The climate of
the northern hemisphere--Britain, at least, and Nova Scotia--was
warmer than now, to judge from the abundance of ferns; and especially
of tree-ferns; but not so warm, to judge from the presence of
conifers (trees of the pine tribe), as the Tropics. Moreover, there
must have been, it seems to me, a great scarcity of animal-life.
Insects are found, beautifully preserved; a few reptiles, too, and
land-shells; but very few. And where are the traces of such a
swarming life as would be entombed were a tropic forest now sunk;
which is found entombed in many parts of our English fens? The only
explanation which