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pudding-stone. The author has had the satis-
faction of seeing one of the Deccan in the gan-
gart, the pebbles being an unctuous quartz ap-
proaching to chalcedony, as in the singular
sandstone of Egypt ; but some seemed impreg-
nated with iron, so as to bear some appearance
of imperfect light brown jasper. A little frag-
ment seemed to be siderous slate.

Anthracite is by Mr. Kirwan called native
mineral carbon. He observes, that the kind
found at Lischwitz, in extensive strata, and that
of Strido in Tuscany, are among the most pure.
Kilkenny coal. He rightly classes the Kilkenny coal as an An-
thracite ; and, by his analysis, it must be one of
the purest, as it contains no less than 97 of car-
bon. But it seems of a different structure from
the anthracite found on the continent, having a
far more compact appearance, with a metallic
lustre at once more bright and steady; nor is it
so brittle, nor so ready to stain the fingers.
What is called the culm of Wales by Mr. Kir-
wan, and which he regards as a variety of this
Swansea coal, species, is probably the Swansea coal, of which



MODE II. ANTHRACITE.

some kinds have a singular and highly metallic
lustre, approaching even to some iron ores of
Elba.

STRUCTURE I. ANTHRACITE.

Aspect 1. Compact. From Alliers, Mont
Blanc.

From little St. Bernard, accompanied by fine
slate with vegetable impressions.

Aspect 2. Laminar. From Regny, near St.
Simphorien. Other sites of both kinds are above
mentioned ; that of Kongsberg, in Norway, mixed
with native silver, being among the most interest-
ing.

STRUCTURE II. KIRWANITE.

The chief differences of this structure have been
already mentioned. Mr. Kirwan observes, that
when fresh broken it frequently appears of a vio-
let colour. Its lustre he estimates at 4, or metal-
lic ; while that of anthracite is from 3 to 4 ap-
proaching metallic. The fracture is foliated, but
the course of the plates variously, confusedly di-
rected, as in some kinds of common coal. Its
fragments are often coated with whitish illinitions ;

VOL. i. 2 o



DOMAIN VI. CARBONACEOUS.

it will not burn till wholly ignited, and then slowly
consumes without caking or emitting flame or
smoke. The ashes are reddish and few.

Our learned author unaccountably omits the
nature of the rock and gangart ; nor does he re-
pair the deficiency in his geological essays.

Aspect 1. Kirwanitefrom Kilkenny.
The same, with the gangart and specimens of
the incumbent rocks.

Aspect 2. The Swansea kind also burns very
slow, without flame, and yields a strong and lasting
mass of heat, with a glowing colour. Swansea is
in the county of Glamorgan, South Wales, in a
more southern latitude than Kilkenny.

Kirwanite from Swansea.



MOJ3E III. COAL.



MODE III. COAL.

This useful substance, which may be said to Sites,
form the gold mines of England, is not only par-
ticularly abundant in the British dominions, but
widely diffused over many parts of the world.
The Netherlands and France seem to follow
Great Britain in tliis mineral wealth ; but it also
appears in the north of Italy, and various parts
of Germany, as Silesia and Hessia*. It has been
used in the north of China from time immemo-
rial, and is not unknown in Japan. Its discovery
in Australasia would add little to the advantages
of a new country abounding in wood. Con-
cerning the coal of Africa, nothing seems to be
reported. In the territory of the United States
of America, coal is said to abound on both sides
of the James river, but particularly in Virginia,
and towards the Ohio. In the isle of Cape Bre-
ton there is an extensive bed of coal, which is
chiefly used for ballast.

Coal appears to have been anciently known, Ancient use,

* There is a mine of excellent coal in limestone, in the hill
of St. Gingoulph, near Geneva, pronounced, aa Saussure observes,
324, St. Gingo, probably the source of a ludicrous oath in
England, because the first reformers were educated at Geneva.

2 O 2



,5()4 BOMAIN VI. CARBONACEOUS.

not only in China, but in other countries. So-
linus * evidently indicates the use of coal, when,
mentioning the medical waters at Bath, he says
they are dedicated to Minerva, " in whose temple
the perpetual fire does not leave embers, but
is changed into rocky lumps." This pretended
miracle was the natural progress of a coal fire,
caked into hard cinders, instead of the soft em-
bers of wood. The abundance of coal in the
neighbourhood of Bath also favours this suppo-
sition. Nay, Theophrastus mentions that the
smiths of Greece sometimes used a black stone
for their fires, which must have been coal f. In
England it seems to have been in common use in
the twelfth century ; but still more early in
Flanders.

Coal forms prodigious strata, generally rather
descending than rising ; but the hill of St. Gilles,
near Liege, may be said to be chiefly composed
of coal, of which there are not less than 50 or
60 strata. The deepest mines known, are said
to be those of the country of Namur, some of

* Cap. 25.

f* He says it was found in Liguria, as was amber, and also in
Elis j and he speaks of its use as common among the smiths. For
that of Liguria, see Mode iv. Gagas whence the name of jet, as
first found there, was near Chimera, probably a pseudovolcano,
arising from inflamed coal.



MODE III. COAL.



which descend two thousand four hundred feet,
or about half a mile. The semidiameter of the
globe is about 3500 miles ; so that our know-
ledge, comparatively, would only extend to the
outward texture of the paper, of a common
globe three feet in diameter.

Mr. Kirwan has, with his usual accumulated Soil*,
reading, discussed the various soils in which coal
appears ; but an enumeration of the different
beds of clay and stone, would little interest the
general reader, while the scientific may consult
his work*. The beds which immediately co-
ver coal, and are thence called its roof, are shale,
(a kind of clay-slate,) and argillaceous sand-
stone. Both contain impressions of vegetables,
generally such gigantic ferns and reeds as at pre-
sent astonish the traveller in the tropical regions.
The strata on which coal reposes, which are
thence called floor, sole, or pavement, are some-
times shale, or indurated clay; but more fre-
quently sandstone; and often the red ferrugi-
nous kind, which is esteemed most ancient. The
shells are chiefly those of rivers, and seldom those
of the sea. It is now well known, from the ex-
periments of Mr. Hatchet, that this substance is
of vegetable origin ; and it is a singularity, but
upon which no general theory can be con-

* Geol. Ess. p. 290.



DOMAIN VI. CARBONACEOUS.

structed, that the chief beds of coal occur near
the mouths of great rivers, and in a kind of pro-
portion to their relative size. Thus the immense
Rhine, which seems, like many other powerful
streams, to have more than once altered its estu-
ary, has in its vicinity rocks of coal at least 80
feet in thickness; while more moderate strata
are found near the Rhone, the Clyde, the Forth,
the Tyne, the Severn. In some instances the
form of the coal district is that of an isosceles
triangle, the vertex being towards the sea. In
savage countries, darkened with immense fo-
rests, and where wood is only a superfluous
weed, the quantity of trees overturned by age,
tempests, and inundations, exceeds all imagina-
tion. On the Missouri, there is said to be a
bridge, not less than three miles in length, form-
ed by successive trunks of trees, which have been
stopped in their progress ; and the soil near its
mouth may be said to be formed of alternate
strata of timber and mud, which may probably
become coal and shale, for the use of nations to
be born, after a period of many thousand years,
and who, perhaps, may faintly trace in their
annals some niemory of a celebrated ancient na-
tion called Britons.

But this is merely an excursion of theory, and
the origin of coal is far from being precisely
ascertained. It occurs in such places, and with



MODE nr. COAL.



such circumstances, as, like the other works of
nature, seem calculated to confound the faint
light and puny pride of human reason.



Patrin, with his usual ingenuity, enumerates Patrm'sre.

* marks.





mark*.

some of the most striking features, which accom-
pany this important formation.

" Many similar circumstances every where
accompany beds of coal.

" 1. It is known that this deposit must have
been made in still water, and that it has been found
on the sides of the soil which has served it for
base. In general, beds of coal have their extre-
mities even with the ground, they descend ob-
liquely; they assume in their depth nearly a
horizontal position, afterwards to ascend on the
opposite side ; so that by taking away, in idea,
all the soil which covers them, they will be found
to have nearly the form of a boat : it has been
remarked also, that they are thicker at their
depth than at their ends.

" This disposition is manifest in a great num-
ber of mines, and especially in the vast coal
mines in the neighbourhood of Liege.

" 2. A bed of coal is never single : at White-
haven in England there are 20, one above an-
other; at Liege there are reckoned 60 *; three

* At Gilmerton, near Edinburgh, there is the same number.
Williams, i. 41.



558 DOMAIN VI. CARBONACEOUS.

or four are most commonly found, and in general
of nearly an equal thickness.

" 3. Each bed of coal is separated from the
others by several rocky strata, which are nearly
the same in all coal mines.

" Those which form the roof and the wall,
are always of a schistose argillaceous substance,
a kind of friable schistus, almost always sulphure-
ous : afterwards follow strata of micaceous sand-
stone, which seem derived, at least in part, from
the detritus of the primitive mountains of the
neighbourhood.

" These strata of sandstone are often separated
by small schistose layers, which contain some
symptoms of coal ; they are both often repeated
between two beds of coal.

" It is a general observation, and almost with-
out^ exception, that the schistose layers, and
especially those which serve as a roof to the
coal, bear impressions of vegetables, particularly
capillaria, ferns and reeds, for the most part ex-
otic. This circumstance has led several natural-
ists to think, that coal itself is composed of the
remains of vegetables - y but this opinion appears
to me to present great difficulties *."f

* " One of the facts, which is most opposite to it, is the obser-
yation made at Santa-Fe-de-Bogota, by the naturalist le Blond, who

f Patrin, Min. v. 317.



MODE III. COAL, 5 ()9

Some select observations concerning coal may
be added from various authors.

By Mr. Kirwan's experiments coal commonly
consists of about 60 carbon and 40 bitumen*.

Though coal has never been found crystallised, structure.
it seems to split into regular cubes ; and another
singularity in its structure has recently been ob-
served, that between the layers of a bright bitu-
minous appearance there are thin plates of a
velvety lustre, bearing a strict resemblance to
charcoal. Coal sometimes contains in little ca-
vities, crystals of calcareous spar, perhaps infil-
trated from incumbent limestone. These crys-
tals, towards their summits, present little black
zones, arising from the coaly impregnation. Ga-
lena, or sulphate of lead, is also found in the coal
of Buckinghamshire. Pyrites are common in
most kinds of coal ; and, perhaps, the beautiful
iridescent illinitions, which in some rare in-

informs us that beds of coal are there found at an elevation of 13,200
feet perpendicular. When the ocean reached such a height, there
would be above its level but a small number of islands scattered
over the face of the globe ; and it is not any how seen, how the
small quantity of vegetables, which had been accidentally brought
from these summits of mountains, into this immense ocean* could
have formed the thinnest bed of coal, or even of simple turf." Is not
this coal of Santa-Fe anthracite ?

* Bitumen long retains its properties. That found on the bricks
of Babylon, where it was used as a mortar or cement, still burns, as
Mr. Parkinson observed, with a strong bituminous scent.



570 DOMAIN VI. CARBONACEOUS.

stances equal all the colours of the richest gems,
may arise from the iron and sulphur, as they
greatly resemble those of the beautiful ores of
Elba.

Oxyd of copper has also been found in coal
* at Schemnitz in Saxony ; cinnabar in that of
Idria; native silver in that of Hessia; nay, gold
decorates the coal of Reichenstein in Silesia. It
is also said that antimony is found in that of the
isle called Bras d'or, near Cape Breton in Ame-
rica *.

Werner's ar- Werner has arranged one species of coal un-
rangement. j er ^jg g erms graphite, namely the glance coal ;
which he again subdivides into the conchoidal
and the slaty. Glance, applied in the German
sense to some ores, and a kind of coal, implies
that they have a peculiar bright lustre ; and his
/ glance coal with the colour of tempered steel, or
a bright variable blue, and which burns without
flame or smell, is the same with that found at
Swansea, here arranged as a structure of anthra-
cite; for it has neither the appearance nor chemi-
cal character of graphite. The slaty glance coal
of V\ r erner, the kohlenblend, or coalblend of other
German mineralogists, is the anthracite. To such
inconsistencies have the forced and unnatural

* Brongniart, ii. 10.



MODE III. COAL.



application of genus and species, to inert mat-
ter, reduced even the ablest authors.

Of common coal, Werner numbers two spe-
cies, the black, and the brown.

The black coal contains six subspecies; 1. Black coal.
Pitch coal ; 2. Columnar coal ; 3. Slaty coal ;
4. Cannel coal ; 5. Foliated coal ; and 6. Coarse
coal. The first is jet which belongs to lithology ;
the second which burns without flame or smell,
is an anthracite, as Voigt allows, and is merely
a rare variety. But from the want of judgement
in distinguishing between the grand and import-
ant substances, and those which are merely tri-
fling and rare varieties, sometimes only excep-
tions or excrescences, the very arrangement of
mineralogic systems is often the source of unne-
cessary embarrassment; the separation of the
pretended species being sometimes radical and
essential, and often of the most trifling and am-
biguous nature ; nay, sometimes as ridiculous as
if the species of trees were to be estimated by the
mosses which grow upon them, the fantastic forms
occasioned by accident, or the cavities hollowed
by the hand of time.

The third subspecies, which in this barbarous
system follows jet, a rare and precious substance,
and columnar coal which is confined to one
hill, the Meissner in Hessia, is that called slate



572



DOMAIN VI. CARBONACEOUS.



coal 9 which is that substance universally known
by the sole name of COAL, which is diffused in
vast exuberance through half the globe, and
supplies nations with necessary fuel and opulent
manufactures ! This instance of want of judge-
ment may be added to numerous others already
observed by Mr. Chenevix *.

The fourth subspecies of Werner is cannel coal,
so called from the enunciation of the word candle,
in Scotland and the north of England, because
its flame is clear and pure, like that of a candle.
By many French writers, and even by Brochant
and Brongniart, it has been strangely confounded
with Kilkenny coaly which being an anthracite
emits no flame ; a clear distinction, indicated by
the simplest chemistry of nature. It is not only
found in several coal mines of the north of En-
gland, but in those of Gilmerton near Edinburgh.
When very pure, it is made into various little
vessels, snuff-boxes, and ink-holders. The Ro-
man writers mention jet, as a chief mineral pro-
duct of Britain, and some suppose that the can-
nel coal is intended, but it would rather appear
to be the real jet found on the eastern coasts,
particularly that of Norfolk, and which, as the
substance is merely bituminous wood, may either

* See his Critique on the Wernerian system, in the Annales dg
Chimie, 180O,.



MODE III. COAL. 573

proceed from parts of the submarine forest, re-
cently observed on the coast of Lincolnshire :
or, as it is very light, may be brought by the
sea from a great distance.

The fifth subspecies, the foliated or laminar, is
found in the Electorate of Saxony, and in Sile-
sia; but it may certainly be observed in almost
every coal pit, as in fact almost all coal may be
said to be slaty ; nay, Werner has arranged it
himself under that subdivision. The last, and
very important subspecies, is coarse coal, which,
forsooth, has been found in the coal works near
Dresden ! It is too well known to many of my
readers, and rather too abundant on the London
wharfs. By such sagacious subdivisions, an im-
pure gold must be regarded as a different metal.
It may, perhaps, be satisfactory to complete
this brief view of Werner's coal, which, like the
magical mirror of Dr. Dee, formed of cannel
coal, represents spirits and species of all kinds
and dimensions, with some account of his other
division, that of brown coal, which contains five
subspecies. 1. Bituminous wood; 2. Earth coal;
3. Alum earth; 4, Common brown coal; and
5. Moor coal.

The first is an important and widely diffused
substance which may be said to form rocks, or



574 DOMAIN VI. CARBONACEOUS.

rather mountain masses, by the Germans called
Bergarts; for as rocks may be formed of shells
and other animal substances, so they may be
constituted of the venerable remains of primeval
vegetation. This kind is the Bovey coal of En-
gland ; and in the Prussian amber mines is found
with adhering amber. It is the Surturbrand
of Iceland where it abounds; and is diffused
through many parts of Germany, France,
Russia, Siberia, and other grand regions of the
world.

The second subspecies, earth coal, is sometimes
found with the former, being merely bituminous
wood more decomposed. The third, or alum
earth is certainly a most capricious alteration,
as he had formerly and properly arranged it
among the argils, and it ought in lithology to
stand at the very head of that class. It may
have been used as a fuel, as orsten is in Ireland;
and, perhaps, Mr. Werner may, in his annual
almanack of classification, arrange that lime-
stone among the coals. The fourth subspecies,
common brown coal, is, by Mr. Jameson's own
account, the same with the first or bituminous
wood, being found at Bovey, and in Prussia,
with amber -, so that it can hardly be called a
variety, certainly not a diversity. The^/A, or



MODE III. COAL.



last subspecies, that of Moor coal, is again a mere
variety of bituminous wood, but more brittle, as
it is mingled with reeds.

The author must confess, that when he had
perused Werner's account of the coals, his ideas
of the subject were far more confused than ever
they were before; so that he seemed with great.
study to have learned ignorance. This effect must
necessarily arise, when subjects of the utmost
importance, and of the most trifling minuteness,
are presented to the mental eye, as of equal mag-
nitude. By the unhappy microscope of external
characters, an insect may appear like an ele-
phant ; while common sense and chemistry can
alone present the objects as they really are. It
is the chief, if not the only, use of systems in
natural history, to assist the memory; and for
this purpose, that the faculty may not be strained
and overpowered, it is the office of a judicious
arrangement, to present the chief objects in the
fore-ground, while the others are marked at gra-
dual distances, that the mental eye may repose,
as upon a landscape, painted by a master artist.

But to return to a more immediate view of the Soil*.
subject. It is not a little remarkable that dif-
ferent qualities of coal are found in different
strata of dissimilar rocks, thus confirming an
observation already made, that the quality of



576 DOMAIN VI. CARBONACEOUS.

mineral substances is often influenced by their
gangarts. Mr. Kirwan has observed, and he
has illustrated the observation by many ex-
amples, that the soils containing coal are chiefly
clay and sandstone, often both together; which
are followed by the rarer instances of coal found
under trap or basaltin, which may also assume
the form of amygdalite; or, by the coarseness of
the particles, become a basalton or grunstein.
Thick beds of coal have also been found amid
the strata of limestone. As the theme is of great
importance to national and individual wealth
and prosperity, it may be proper to subjoin the
brief general view by Brongniart.

" The coal regions follow in general the same
order of composition. 1. Psammites (micaceous
and ferruginous sandstone, with a cement gene-
rally of argil,) often large grained : they are not
only composed of quartz and mica, but of frag-
ments of all kinds of rocks, particularly of fel-
spar. 2. Argillaceous and micaceous schisti ;
presenting on their plates impressions of fishes
and vegetables, which generally belong to the
families of ferns and grasses. 3. Beds of marl,
carbonated lime, or indurated clay. 4. A kind
of secondary argillaceous porphyry, which con-
tains branches, roots, and even entire petrified
trees. 5. Argillaceous iron ore. 6. Rolled



MODE III. COAL. 577

pebbles enveloped in ferruginous sand." * He
afterwards observes, that the limestone which
contains coal, often becomes black from inhala-
tions of the bitumen, while the inherent shells
are of a white colour.

A remarkable circumstance in coal mines is Slips or dykes,
the frequent occurrence of what our miners call
slips or dykes, while the French call them creins
or failles, consisting of indurated clay, basaltin,
called whin in Scotland, and sometimes of sand-
stone. These are sometimes of great extent, and
a whin-dyke is said to pass across the estuary of
the Forth, from East Lothian to Fife, a distance
of 10 or 12 miles. These slips intersect the
strata of coal, almost at right angles; and ge-
nerally derange them, in regard to elevation, the
stratum of coal being higher and lower on the
different sides of this interruption. It seems a
general observation that the strata always sink,
on what may be called the back of the slip,
which seems to indicate that the matter was
ejected from beneath, and that the consequent
cavity had occasioned the subsidence on that
side. These slips sometimes contain fragments
of coal f. They appear in the section of the

* Min. ii. 6.

\ Near the slips the quality of the coal changes ; it sometimes
becomes iridescent 5 still nearer it splits and is friable j then be-

VOL. I. 2 P



578



DOMAIN VI. CARBONACEOUS.



noted hill of St. Gilles, near Liege. Genneta
has inferred that there are in this hill not less
than 61 beds of coal which are salient, or in the
mining language rise to the day> at distinct dis-
tances, but only 23 are worked. The coal
mines of Anzin, near Valenciennes, described
by Daubuisson, present singular large zigzags
which seem to defy all theory, except the prodi-
gious power of steam, arising from internal fires
and waters, and acting while the beds were yet
soft.
Coal mines of The limits and nature of this work do not per-

England.

mit a description of the important coal mines,
even of England. Those of Newcastle are the
most celebrated, as they have supplied the capi-
tal for many ages. The land which covers these
mineral treasures, is often fertile, and lies on an
argillaceous sandstone, which forms excellent
grindstones, not only common in England, but
exported to other countries. Even the roads are
grand monuments of human industry, the tra-
veller being astonished to see large carts loaded
with coal, proceeding without horses or guides,
on wheels adapted to wooden ways defended
with iron. The coal mines of Whitehaven, on
the western coast, are the more remarkable, as

comes dull, earthy, and, a& it were, identified with the slip. J. des
Mine*, No. 13, p. $0.



MODE III. COAL.



they are continued for a space of more than 1200
yards, or two thirds of a mile under the sea ; a
situation like that of a mine in Cornwall, where
the raging waves are heard over head, most ter-
rible to the imagination. The most celebrated
coal mines of France are those of St. Etienne, in
the department of the Loire, which have been
worked for many centuries. Those of Flanders
are also of ancient reputation: and, perhaps,
our attention to this valuable substance was,



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