ove the level of the highest river-floods of the present day.

The _lignite_, when recently detached from the beds, is pretty compact,
but soon splits into rhomboidal pieces, which again separate into slates
more or less fine. It burns with a very fetid smell, somewhat resembling
that of phosphorus, with little smoke or flame, leaving a brownish-red
ash, not one-tenth of the original bulk of the coal. The blacksmith
found it unfit for welding iron when used alone, but it answered when
mixed with charcoal, although the stench it created was a great
annoyance. [Sidenote: 48] Different beds, and even different parts of
the same bed, presented specimens of the fibrous brown-coal, earth-coal,
conchoidal brown-coal, and trapezoidal brown-coal of Jameson. Some of
the pieces have the external appearance of compact bitumen, but they
generally exhibit, in the cross fracture, the fibrous structure of wood
in concentric layers, apparently much compressed. Other specimens have a
strong external resemblance to charcoal in structure, colour, and
lustre. A frequent form of the lignite is that of slate, of a dull,
brownish-black colour, but yielding a shining streak. The slate is
composed of fragments, resembling charred wood, united together by a
paste of more comminuted woody matter, mixed, perhaps, with a small
portion of clay. In the paste there are some transparent crystals of
sulphate of lime, and occasionally some minute portions of a substance
like resin. These shaly beds bear a strong resemblance to peat, not only
in structure but also in the mode of burning, and in the light whitish
ashes which are left. The external shape of stems or branches of trees,
is best preserved in some fragments impregnated with slate-clay, and
occasionally with siliceous matter, which occur imbedded in the coal.
The bark of these pieces has been converted into lignite. Some of them
exhibit knots, such as occur where a branch has decayed, and others
represent the twists and contortions of wood of stunted growth. The
lignite is generally penetrated by fibrous roots, probably
_rhizomorpha_, which insinuate their ramifications into every crevice.

The beds of lignite appear to take fire spontaneously when exposed to
the atmosphere. They were burning when Sir Alexander Mackenzie passed
down the river in 1789, and have been on fire, in some part or other of
the formation, ever since. In consequence of the destruction of the
coal, large slips of the bank t