this benefit is the direct result of physical
changes which affected the earth at those remote
periods of time, when the first forms of
vegetable life appeared upon its surface.
The important uses of coal and iron in administering
to the supply of our daily wants, give
to every individual amongst us, in almost every
moment of our lives, a personal concern, of
which but few are conscious, in the geological
events of these very distant eras. We are all
brought into immediate connection with the vegetation
that clothed the ancient earth, before
one-half of its actual surface had yet been formed.
The trees of the primeval forests have not,
like modern trees, undergone decay, yielding
back their elements to the soil and atmosphere
by which they had been nourished; but, treasured
up in subterranean storehouses, have been
transformed into enduring beds of coal, which in
these later ages have become to man the sources
of heat, and light, and wealth. My fire now
burns with fuel, and my lamp is shining with the
light of gas, derived from coal that has been
buried for countless ages in the deep and dark
recesses of the earth. We prepare our food, and
maintain our forges and furnaces, and the power
of our steam-engines, with the remains of plants
of ancient forms and extinct species, which were
swept from the earth ere the formation of the
transition strata was completed. Our instruments
of cutlery, the tools of our mechanics, and
the countless machines which we construct, by
the infinitely varied applications of iron, are derived
from ore, for the most part coeval with, or
more ancient than the fuel, by the aid of which
we reduce it to its metallic state, and apply it
to innumerable uses in the economy of human
life. Thus, from the wreck of forests that waved
upon the surface of the primeval lands, and
from ferruginous mud that was lodged at the
bottom of the primeval waters, we derive our
chief supplies of coal and iron ; those two
fundamental elements of art and industry, which
contribute more than any other mineral production
of the earth, to increase the riches, and
multiply the comforts, and ameliorate the condition
of mankind.
Chapter VIII.
Strata o f the Secondary Series,
We may consider the history of secondary, and
also of tertiary strata, in two points of view : the
one, respecting their actual state as dry land,
destined to be the habitation of man; the other,
regarding their prior condition, whilst in progress
of formation at the bottom of the waters,