act
that the peat, thus condensed, flakes to pieces by a short immersion in
water.

The great advantage of Exter's and Elsberg's method consists in avoiding
what most of the others require, viz.: the expensive transportation and
handling of fresh peat, which contains 80 to 90 _per cent._ of water,
and the rapid removal of this excess of water before the manufacture. In
the other methods the surplus water must be slowly removed during or
after condensation.

Again, enough peat may be air-dried and stored during summer weather, to
supply a machine with work during the whole year.

Its disadvantages are, that it requires a large outlay of capital and
great expenditure of mechanical force. Its product is, moreover, not
adapted for coking.

B.--_Condensation without Pressure._

The methods of condensing peat, that remain to be described, are based
upon radically different principles from those already noticed. In
these, little or no pressure is employed in the operations; but
advantage is taken of the important fact that when wet or moist peat is
ground, cut or in any way reduced to a pulpy or pasty consistence, with
destruction of the elastic fibres, it will, on drying, shrink together
to a coherent mass, that may acquire a density and toughness much
greater than it is possible to obtain by any amount of mere pressure.

The various processes that remain to notice are essentially reducible to
two types, of which the French method, invented by Challeton, and the
German, invented it appears by Weber, are the original representatives.
The former method is only applicable to earthy, well-decomposed peat,
containing little fibre. The latter was originally applied to fibrous
moss-peat, but has since been adapted to all kinds. Other inventors,
English, German, and American, have modified these methods in their
details, or in the construction of the requisite machinery, rendering
them more perfect in their execution and perhaps more profitable in
their results; but, as regards the essential principles of production,
or the quality of product, no advance appears to have been made beyond
the original inventors.

a. _Condensation of Earthy Peat._

_Challeton's Method_ consists essentially in destroying the fibres, and
reducing the peat by cutting and grinding with water to a pulp; then
slowly removing the liquid, until the peat dries away to a hard coherent
mass. It provides also for the purification of the peat from earthy