63 _per cent. of the
organic matter_, and the increase of carbon is related to its ripeness
and density. The poorest, youngest peat, has the same proportion of
carbon as exists in wood. It does not, however, follow that its heating
power is the same. The various kinds of wood have essentially the same
proportion of carbon, but their heating power is very different. The
close textured woods--those which weigh the most per cord--make the best
fuel for most purposes. We know, that a cord of hickory will produce
twice as much heat as a cord of bass-wood. Peat, though having the same
or a greater proportion of carbon, is generally inferior to wood on
account of its occupying a greater bulk for a given weight, a necessary
result of its porosity. The best qualities of peat, or poor kinds
artificially condensed, may, on the other hand, equal or exceed wood in
heating power, bulk for bulk. One reason that peat is, in general,
inferior to wood in heating effect, lies in its greater content of
incombustible ash. Wood has but 0.5 to 1.5 _per cent._ of mineral
matters, while peat contains usually 5 to 10 _per cent._, and often
more. The oldest, ripest peats are those which contain the most carbon,
and have at the same time the greatest compactness. From these two
circumstances they make the best fuel.

It thus appears that peat which is light, loose in structure, and much
mixed with clay or sand, is a poor or very poor article for producing
heat: while a dense pure peat is very good.

A great drawback to the usefulness of most kinds of peat-fuel, lies in
their great friability. This property renders them unable to endure
transportation. The blocks of peat which are commonly used in most parts
of Germany as fuel, break and crumble in handling, so that they cannot
be carried far without great waste. Besides, when put into a stove,
there can only go on a slow smouldering combustion as would happen in
cut tobacco or saw-dust. A free-burning fuel must exist in compact lumps
or blocks, which so retain their form and solidity, as to admit of a
rapid draught of air through the burning mass.

The bulkiness of ordinary peat fuel, as compared with hard wood, and
especially with coal, likewise renders transportation costly, especially
by water, where freights are charged by bulk and not by weight, and
renders storage an item of great expense.

The chief value of that peat fuel, which is simply cut from the bog, and
dried without artificial