acre. This is only one eightieth part of the quantity of peat sometimes
found on the same area. It is true that a yard of peat and a yard of
wood are not the equivalents of each other, but the fuel on an acre of
deep peat is worth much more than that on an acre of the best woodland.
Besides this, wood is perishable, and the quantity of an acre cannot be
increased beyond the amount just stated; peat is indestructible, and the
beds are always growing. See post, Chap. IV. Cold favors the conversion
of aquatic vegetables into peat. Asbjornsen says some of the best peat
he has met with is from a bog which is frozen for forty weeks in the
year.

The Greeks and Romans were not acquainted with the employment of peat as
fuel, but it appears from a curious passage which I have already cited
from Pliny, N. H., book xvi., chap. 1, that the inhabitants of the North
Sea coast used what is called kneaded turf in his time. This is the
finer and more thoroughly decomposed matter lying at the bottom of the
peat, kneaded by the hands, formed into small blocks and dried. It is
still prepared in precisely the same way by the poorer inhabitants of
those shores.

But though the Low German tribes, including probably the Anglo-Saxons,
have used peat as fuel from time immemorial, it appears not to have been
known to the High Germans until a recent period. At least, I can find
neither in Old nor in Middle High German lexicons and glossaries any
word signifying peat. Zurb indeed is found in Graff as an Old High
German word, but only in the sense of grass-turf, or greensward. Peat
bogs of vast extent occur in many High German localities, but the former
abundance of wood in the same regions rendered the use of peat
unnecessary.] and of smaller animals, insects, and birds, in destroying
the woods. [Footnote: See Chapter II., post.]