Oliver Goldsmith.

A history of the earth and animated nature: With notes from the ..., Volume 1 online

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we went to the end of the cave, the distance of which,
from the entrance, we found to be fifty-five yards, the
height not being in general more than seven or eight
feet. The inside was lined with melted matter dis-
posed in various singular forms."

' Kircher Mund. sub. 1 12. I have translated a part
of Kircher'a description, rather than Toumefort'e, as
the latter was written to support an hypothesis.



some white^ some green ; and all receding in
due perspective. Thev struck us with the
more amazement, as we knew them to be
mere productions of nature, who, hitherto in
solitude, had, in her playful moments, dressed
the scene as if for her own amusement.

'^But we had as jet seen but a few of the
wonders of the place; and were introduced
only into the portico of this amazing temple.
In one comer of this half-illuming recess
there appeared an opening of about three
feet wide, which seemed to lead to a place
totally darky and that, one of the natives
assured us, contained nothing more than a
reservoir of water. Upon this we tried, by
throwing down some stones^ which mmbling
along the sides of the descent for some time,
the sound seemed at last quashed in a bed
of water. In order, however, to be more
certain, we sent in a Levantine mariner, who,
by the promise of a good reward^ with a
flambeau in his hand, ventured into this nar-
row aperture. ^After continuing within it
for about a quarter of an hour, he returned
carrying some beautiful pieces of white spar
in lus handf which art could neither imitate
nor equal. Upon being informed by him
that the place was full of these beautiful in-
crustations, I ventured in once more with
him for about fifty paces, anxiously and
cautiously descending by a steep and dan-
gerous way. Finding, however, that we
came to a precipice which led into a spadoua
amphitheatre, if I may so call it, still deeper
than any other part, we returned, and being
provided with a ladder, flambeaux, and other
things to expedite our descent, our whole
company, man by man, ventured into the
same opening, and descending one after
another, we at last saw ourselves altogether
in the most magnificent part of the cavern.

*'Our candles being now all lighted up,
and the whole place completely illuminated,
never could the eye be presented with a more
glittering, or a more magnificent scene. The
roof all hung with solid icides, transparent
as glass, yet solid as marble. The eye could
scarcely reach the lofty and noble ceiling;
the sides 'Wcrc regularly formed with spars;
and the whole presented the idea of a magni-
ficent theatre, illuminated with an immense
profusion of lights. The floor consisted of
solid marble; and in several places magnifi-
cent columns, thrones, altars, and other
objects appeared, as if nature had designed
to mock the curiosities of art. Our voices,
upon speaking or singing, were redoubled to
an astonishing loudness, and upon the firing
of a gun, the noise and reverberations were
almost deafening. In the midst of this
grand amphitheatre rose a concretion of about



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THE BARTH.



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fifteen feet higb, that in some measure re-
sembled an altar; from which, taking the
hint, we caused mass to be celebrated there.
The beautiful columns that shot up round
the altar appeared like candlesticks; and
many other natural objects represented the
customary ornaments of this sacrament.

''Below even this spacious grotto there
seemed another cavern; down which I ven-
tured with my former mariner, and descended
about fifty paces by means of a rope. I at
last arrived at a small spot of level ground,
where the bottom appeared different firom
that of the amphitheatre, being composed of
a soft clay yielding to the pressure, and in
which I thrust a stick to about six feet deep.
In this, however, as above, numbers* of the
most beautiful crystals were formed, one of
which particularly resembled a table. Upon
our egress from this amazing cavern, we per-
ceived a Greek inscription upon a rock at
the mouth, but so obliterated by time that
we could not read it. It seemed to import
that one Antipater, in the time of Alex-
ander, had come thither, but whether he
penetrated into the depths of the cavern, he
does not think fit to inform us.**

Such is the account of this beautiful scene
as communicated in a letter to Kircher. We
have another, and a more copious description
of it by Touruefort, which is in everybody's
hands; but I have given the above, both
because it was communicated by the first
discoverer, and because it is a simple narra-
tive of fiicts, without any reasoning upon
them. According to Toumefort's account,
indeed, we might conclude from the rapid
growth s>f the spars in this grotto that it
must every year be growing narrower, and
that it must in time be choked up with them
entirely; but no such thing has happened
hitherto, and the grotto at this day continues
as spacious as we ever knew it.

This is not a place for an inquiry into the
seeming vegetation of those stony substances,
with which this and almost every cavern are
incrusted ; it is enough to observe, in general,
that they are formed by an accumulation of
that little gritty matter which is carried
thither by the waters^ and which in time
acquires the hardness of marbla What in
this place more imports us to know, is how
these amazing hollows in the earth came to
be formed And I think, in the three in-
stances above mentioned, it is pretty evident,
that their excavation has been owing to
water. These finding subterraneous jiassages
under the earth, and by long degrees hollow-
ing the beds in which they flowed, the ground
above them has slipped down closer to their
rurfacc, leaving the upper layers of the earth



or stone stiU suspended: the ground that
sinks upon the fisice of the waters forming
the floor of the cavern ; the ground or rocl^
that keeps suspended, forming the roof: and
indeed, there are but few of these caverns
found without water, either within them, or
near enough to point out their formation.



CHAP. vni.

OF MINIS, DAXP8, AND MIKEBAL VAPOUBS.

The caverns which we have been describ-
ing, generally carry us but a very little way
below the surface of the earth. Two hun-
dred feet, at the utmost, is as much as the
lowest of them is found to sink. The per-
pendicular fis8iu%s run much deeper; but
few persons have been bold enough to ven-
ture down to their deepest recesses; and
some few who have tried have been able to
bring back no tidings of the place, for un-
fortunately they left their lives below. The
excavations of art have conducted us much
farther into the bowels of the globe. Some
mines in Hungary are known to be a thou-
sand yards perpendicular downwards; and I
have been informed by good authority, of a
coal mine in the north of England, a hun-
dred yards deeper still.

It is beside our present purpose to inquire
into the peculiar contrivance and construc-
tion of these, which more properly belongs
to the history of fossils. It will be sufficient
to observe in this place, that as we descend
into the mines, the various layers of earth
are seen as we have already described them ;
and in some of these are always found the
metals or minerals for which the mine has
been dug. Thus frequently gold is found
dispersed and mixed with clay and gravel ; *
sometimes it is mingled with other metallic
bodies, stones, or bitumens;' and sometimes
united with that most obstinate of all sub-
stances, platina, from which scarce any art
can separate it. Silver is sometimes found
quite pure,* sometimes mixed with other
substances and minerals. Copper is found
in beds mixed with various substances, mar-
bles, sulphurs, and pyritea Tin, the ore of
which is heavier than that of any other
metal, is generally found mixed with every
kind of matter:* lead is also equally com-
mon: and iron, we well know, can be ex-
tracted from all the substances upon earth.

« Ulloa, Yol. il. p. 470. • Ibid.

, * Macqaer's ChemUtrj, p. 3 1 6. ' Hiirs FossUb, p. 628.



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36



HISTORY OF



The variety of substances wbioh are thus
found in the bowels of the earth, in their
native state, have a very different appear-
ance from what they are afterwards taught
to assume by human industry. The richest
metals are very often less glittering and
splendid than the most useless marcasites; ,
and the basest ores are generally the most
beautiful to the eye.

This variety of substances, which compose
the internal parts of oar globe, is productive
of equal varieties, both above and below its
surface. The combination of the different
minerals with each other, the heats which
arise from their mixtui'e, the vapours they
diffuse, the fires which they generate, or the
colds which they sometimes produce, are all
either noxious or salutary to man ; so that
in this great elaboratory of nature, a thou-
sand benefits and calamities are forging, of
which we are wholly unconscious; and it is
happy for us that we are so.

Upon our descent into mines of considera-
ble depth, the cold seems to increase from
the mouth as we descend ; * but after passing
very low down, we begin by degrees to oome
into a warmer air, which sensibly grows
hotter as we go deeper, till at last, the
labourers can scarcely bear any covering as
^ they continue working.

This difference in the air was supposed by
Boyle to proceed from magazines of fire that
lay nearer the centre, and that diffused their
heat to the adjacent regions. But we now
know that it may be ascribed to more obvious
causes. In some mines, the composition of
the earth all aroimd is of such a nature, that
upon the admission of water or air, it fre-
quently becomes hot, and oflen bursts out
into eruptions. Besides this, as the external
air cannot readily reach the bottom, or be
renewed there, an observable heat is per-
ceived below, without the necessity of recur-
ring to the central heat for an explanation.

Hence, therefore, there are two principal
causes of the warmth at the bottom of mines:
the heat of the substances of which the sides
are composed; and the want of renovation
in the air below. Any sulphureous sub-
stance, mixed with iron, produces a very
great heat, by the admission of water. If,
for instance, a quantity of sulphur be mixed
with a proportionable share of iron filings,
and both kneaded together into a soft paste,
with water, they will soon grow hot, and at
last produce a fiame. This experiment, pro-
duced by art, is very commonly effected
within the bowels of the earth by nature.
Sulphurs and irons are intimately blended
together, and want only the mixture of



» Boyle, vol. iii. p. 232.



water or air to excite their heat ; and this,
wiien once raised, is oomniunicated to all
bodies that lie within the sphere of their
operation^ Those beautiful minerals called
marcantea and pyrites, are often of this com-
position; and wherever they are found,
either by imbibing the moisture of the air,
or having been by any means combined witli
water, they render the mine considerably hot.'

The want of fresh air also, at these depths,
is, as we have said, another reason for their
being found much hotter. Indeed, without
the assistance of art, the bottom of most
mines would, from this cause, be insupport-
able. To remedy this inconvenience, the
miners are often obliged to sink, at some
convenient distance from the month of the
pit where they are at work, another pit,
which joins the former below, and which, in
Derbyshire, is called an air-shaft. Through
this the air circulates; and thus the work-
men are enabled to breathe .freely at the
bottom of the place ; which becomes, as Mr.
Boyle affirms, very commodious for respira-
tion, and also very temperate as to heat and
cold.' Mr. Locke, however, who has left
us an account of the Mendip mines, seems
to present a different picture. ''The descent
into these is exceedingly difficult and dan-
gerous; for they are not sunk like wells,
perpendicularly, but as the crannies of the
rocks happen to run. The constant method
is to swing down by a rope placed under the
arms, and clamber along by applying both
feet and hands to the sides of the narrow
passage. The air is conveyed into them
through a little passage that runs along the
sides from the top, where they set up some
tui*fs, on the lee-side of the hole, to catch
and force it down. These turfs being re-
moved to the windy side, or laid over the
mouth of the hole, the miners below pre-
sently want breath, and faint; and if sweet-
smelling flowers chance to be placed there,
they immediately lose their fragrancy, and
stink like carrion.*' An air so putrefying can
never be veiy commodious for respiration.

Indeed, if we examine the complexion of
most miners, we shall be very well able to
form a judgment of the unwholesomeness of
the place where they are confined. Their
pale and sallow looks show how much the
air is damaged by passing through those
deep and winding ways, that are rendered
humid by damps, or warmed with noxious
•exhalations. But although every mine is
unwholesome, all are not equally so. Coal-
mines are generally less noxious than those
of tin; tin than those of copper; but none

* Kircher Hand. Subt. vol. ii. p. 216.
» Boyle, vol. iii. p. 238.



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aro so dreadfully destructive as those of
qoioksilver. At the mines near the village
of Idra, nothing can adequately describe the
deplorable infirmities of such as fill the
hospital there; emaciated and crippled, every
limb contracted or convulsed, and some in a
manner transpiring quicksilver at every pore.
There was one man, says Dr. Pope,' who was
not in the mines above half a year, and yet
whose body was so impregnated with this
mineral, that putting a piece of brass money
in bis mouth, or rubbing it between his
fingers, it immediately became as white as
if it had been washed over with quicksilver.
In this manner all the workmen are killed
sooner or later; first becoming paralytic,
and then dying consumptive: and all this
they sustain for the trifiing reward of seven-
pence a day.

But these metallic mines are not so noxi-
ous from their own vapours, as from those
of the substances with which the ores are
usually imited, such as arsenic, cinnabar,
bitumen, or vitriol. From the fumes of
these, variously combined, and kept inclosed,
are produced those various damps, that put
on so many dreadful forms, and are usually
so &taL Sometimes these noxious vapours
are perceived by the delightful fragrance of
their smell,* somewhat resembling the pea-
blossom in bloom, from whence one kind of
damp has its name. The miners are not de-
ceived, however, by its flattering appear-
ances ; but as they have thus timely notice
of its coming, they avoid it while it con-
tinues, which is generally during the whole
summer season. Another shows its approach
by the burning of the candles, which seem
to collect their flame into a globe of light,
and thus gradually lessen, till they are quite
extinguished. From this, also, the miners
frequently escape; however, such as have
the misfortune to be caught in it, either
swoon away, and are suflbcated, or slowly
recover in excessive agonies. Here also is
a third, called ths /lUmiruUing damp, much
more dangerous than either of the former,
as it strikes down all before it like a flash
of gunpowder, without giving any warning
of its approach. But there is another, more
deadly than all the rest, which is found in
those places where the vapour has been long
confined, and has been, by some accident, set
free. The air rushing out from thence,
always goes upon deadly errands : and scarce
any escape to describe the symptoms of its
operations.

Some colliers in Scotland, working near
an old mine that had been long closed up,
happened, inadvertently, to open a hole into



» Phil. Traiui. vol. ii. p. 678.



• Ibid. p. 375.



it, fi:t>m the pit where ^hey were then em-
ployed. By great good fortune, they at
that time perceived their error, and instantly
fled for their lives. The next day, however,
they were resolved to renew their work in
the same pit, and eight of them ventured
down, without any great apprehensions; but
they had scarcely got to the bottom of the
stairs that led to the pit, but, coming within
the vapour, they all instantly dropped down
dead, as if they had been dbot." Amongst
these unfortimate poor men, there was one
whose wife was informed he was stifled in
the mine : and, as he happened to be next
the entrance, she so far ventured down as
to see where he lay. As she approached
the place, the sight of her husband inspirecl
her with a desire to rescue him, if possible,
from that dreadful situation; though a little
reflection might have shown her it was then
too late. But nothing could deter her; she
ventured forward, and had scarce touched
him with her hand, when the damp pre-
vailed, and the misguided, but fitithful crea-
ture, fell dead by his side.'



* The mode of working coal-mines varies in different
parts of the coantrj, partly on account of the sitoation
of the seams of coal in the groond, and partly on ac«
count of customs peculiar to the spots. That which
we are about to describe is the method usually adopted
in the Newcastle coal field ; the chief sources of infor-
mation on the subject being contained in the evidence
given before the committees of the Houses of Lords
and Commona in 1829 and 1830, by Mr. Buddie and
Mr. Taylor, eminent engineers or coal viewers, and of
large experience in the north of England collieries.

No instances occur in this country of beds of coal
lying so near the surface that they can be iforked in
open day like a stone quarry, nor are they often met
with in the side of a hill, so that the mines can be
pushed forward in a horizontal direction. When,
therefore a coal-field is to be toonj as it is technically
called, that is, when the coals are to be taken out, the
first step is to sink a perpendicular circular shaft, like
a great well, in order to get at the coal, and by which
the miners or pitmen descend, and the coal is brought
to the surface. The sum required for winning a field
of coal, that is, the coal under a certain portion of land
marked out on the surface, is sometimes so consider-
able, and the risk of failure so great, that very few
individuals venture upon it on their sole account.
They are usually won by a company, called adventur-
ers, who take a lease from the proprietor. On the
river Tyne there are only five proprietors, out of the
forty-one collieries, who work their own mines, and on
the river Wear there are only three out of eighteen
collieries; all the rest are in the hands of lessees or
adventurers. The capital is raised by shares, often
of small amount, and being transferable, are constantly
in the market. Collieries vary exceedingly as to the
amount of capital required to win them, the difference
being so great as from £10,000 to £150,000. One of
the difficulties in sinking a shaft is passing through
quicksands; another is the immense quantities of
water which are met with in certain parts of the stra-
tification, generally within forty or fifty fathoms from
the surface, which is always dammed back by a tub.
Mr. Buddie mentions a shaft in which he had to apply
forty fathoms, that is, 240 feet, of cast-iron tubbing*



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38



HISrOBY OF



Thus, the vapours foand beneath the sur-
fiioe of the earth are very various in their
effects upon the constitution : and thej are
not less in their appearance. There are
many kinds that seemingly are no way pre-
judioial to health, but in which the work-



Beaides, one shaft is not sufficient, another heing re-
quired for drawing up the water and for yentilating the
mine.

The depth of the mines is -very Tarioos; in one plaee
near Jarrow, ahout fire miles from the mouth of the
Tjne on its southern bank, the high main coal of the
Tyne is found within 42 feet of the ground, and the
same coal lies under Jarrow lake more than 1200 feet
from the snrlaoe. This great depth is not reached bj
one perpendicular shaft, but a shaft and steam-engine
under ground, with descending inclined planes. A
gseat improvement was made bj this erection of steam-
engines to be worked in the pits underground, and
which first took place in 1804.

The ^it having been sunk to a sufficiently thick seam
of coal, the process of excavating it begins, bj cutting
out the coal laterally in what are called galleries. In
the Newcastle mines large masses of the coal, named
pUlars, are left to support the roof, at short intervals,
but in Staffordshire the whole of the coal is taken awaj,
and the roof of the mine is suffered to fall down, care
being taken to support it so &r as not to endanger the
safety of the workmen. One set of workmen is em-
ployed in digging out the coal, and another in removing
it to the bottom of the shaft, from wheooe it is drawn
up by machinery to the surface. The work of the
miners is very laborious, especially where the seams
are so thin as to prevent their being in an erect posture.

In many collieries, after the whole of the coal has
been got out in the ordinary way of working, they
gradually cut away a part of the pillars of coal which
had been left at intervals, for the support of the roof,
substituting props of timber; and sometimes the whole
of the pillar may be taken away without the roof fidl-
ing in in such a manner as to impede the workman in
other parts of the mine. When the whole of the coal
has beea excavated and the roof does not &11 down,
vast empty spaces or wastes are left, which very gene-
rally after a while, become filled with water, to the
great danger of the adjoining collieries.

The chief accidents to which collieries are exposed,
besides that of the roof and floor coming together, by
the pressure over the places where the coal has been
worked out, are inundations of water, and explosions
of gas. The quantity of water which flows into the
mines is sometimes quite enormous, and the expense
of drawing it off by pumps worked by steam-engines
is one of the heaviest charges of a colliery. Mr.
Buddie sutes that in one with which he is connected,
they draw eighteen times the weight of water which
they do of coal. It very often happens that a mine is
drowned by an accidental opening into an old working
filled with water.

But of all the accidents to which coal-mines are ex-
posed the explosions of inflammable gas or fire-damp
are the most frequent, and by far the most calamitous
in their consequences. All coal, even the charcoaMike
variety called anthracite, appears to contain, in its
natural state while underground, a considerable quan-
tity of free uncombined gas, which it parts with when
Exposed to the air, or when it is relieved from great
superincumbent pressure. The gas is evolved from
the coal in great quantity at the ordinary temperature
of the mines ; and insunces have been known of ex-
plosions on board of ships laden with fresh-worked
coals. Coals lying deep give out more gas than those
near the surface, because there are openings at the
earfaoe by which it escapes ; but in the deep mines it



men breathe freely ; and yet in these, if a
lighted candle be introduced, they immedi-
ately take fire, and the whole cavern at once
becomes one furnace of flame. In mines,
therefore, subject to damps of this kind, they
are obliged to have recourse to a very pe-



cannot have such an outlet, and therefore it accumu-
lates in all the fissures of the stone above the ooal, and
this sort of natural distillation is constantly going on.
The fissures of the roof are in some places very great,
and there are sometimes miles of communication from
one fissure to another: they may be considered as
natural gasometers, and having no outlet, and the pro-
cess of distillation constantly going on, the gas becomes
accumulated in them in a very highly condensed state,
the degree of condensation depending on the thickness
of the surrounding rock and the quantity poured in.
In the course of pursuing the workings, the miners
sometimes cut across one of those fissures, or approach
so near to it, that the intervening rock becomes too
weak to resist the elastic force of the compressed gas ;
it gives way, and then, in either case, the gas rushes
out with immense force. These Uowen, as they are
called, emit sometimes as much as 700 hogsheads of
gas in a minute, and continue in a state of activity for
many months together. Sir James Lowther found a



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