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from the chalk by a bed of bluish potters' clay.
To different parts of its beds distinct names have
been applied, according to their quality, and
the uses for which they are destined. That
which is of a fine grain and compact texture is
called pierre de liais '*: it may be cut in sharp
squares, and resists the weather; the thickness
of its beds seldom exceeds eight inches. The

* In the common dictionaries, liais, and pierre de taille, are
translated freestone. Sandstone is grcs.


pier re de roche is as hard as the liais, but porous
and full of shells; thickness of the beds about
two feet. The lambourde is a tender stone with
a coarse grain $ the beds being about three feet.
These three qualities, and others which we omit,
are often found in the same quarry.

" The quarries which furnish the best build-
ing stone used at Paris, are those of St. Norn in
the park of Versailles; La Chaussee, near St.
Germain en Laye; Poissy; Nanterre; the three
last yielding stones almost as beautiful as the
liais s of Saillancourt, near Pontoise; of Con-
flans Ste. Honorine ; this quarry yields the finest
tender stones, sometimes seven or eight feet in
thickness ; of St. Nicolas, near Senlis, which is
a liais ; of St. Leu and Trossy, department of
Oise, which is a soft stone.

<c The soft kinds are sawed dry, the saw hav-
ing teeth as that used for timber. The hard
kinds are divided by a saw without teeth, by
the means of water and pounded sandstone.
But that they may not decompose in the air,
they must be placed according to their original
beds, for very few will last in the opptosite po*
sition. Several porous and tender kinds are sub-
ject to split by frost. The weight varies accord-
ing to their quality; thus the hard stone of


Meudon is to the tender stone of St. Leu as 24
to 17. This stone being generally impure yields
a bad lime."*

This important rock may be divided into two
structures; the simple or entire, and that min-
gled with shells, or the Conchitic. No example
of the Zoophytic seems to occur in this kind of
limestone, which is of recent formation.


Aspect 1. Fine-grained. From Egypt.
From Caen, Tonnerre, and Nanterre, France.
From Tottenhoe, Bedfordshire.
From Portland.

Aspect 2. Coarse. This is often found in the
same quarries.

From Saillancourt, near Pontoise, in France.

From Portland.

From Scotland.

Yellow, from Lyons, the chief building stone
there used.

* Brongniart, i. 204.



Aspect 1. With nummulites, from Egypt.

With cerites, from Paris.

With various shells, from the vicinity of Bath.

The pierre de taille used at Marseilles is a con-
chitic limestone, of which the quarries are at Cape


The characters of this rock will be given in
some distinct Structures. The combination, as
of the former Modes, is chiefly lime and car-
bonic acid, about 40 of the latter to 50 of the
former; whence the term carbonates of lime. Carbonates of
But the Modes differ in minute particulars, as
already mentioned.

This useful rock abounds in most countries.
It is generally burnt to make lime and mortar;
but is also employed in building, and sometimes
in making roads, though the siliceous substances
be more durable and proper for the latter pur-

* Sauss. 1517.





It is often full of marine shells, and lies super-
incumbent upon slate or sandstone : some have
even confounded compact limestone with sand-
stone. Patrin has observed that the calcareous
deposition was more abundant on the summit of
mountains than on their sides, because the slopes
scarcely received, on a hundred fathoms of sur-
face, the same quantity with ten fathoms of the
level summit*. Hence the latter is sometimes
insulated and separated from that of the plains,
because the thin beds on the sides of the moun-
tains were .worn down by the waters; and as the
summits of the mountains attract clouds, so un-
der the primeval waters they must have attracted
the various substances contained in them.

The calcareous chain of the Pyrenees is far
higher than the granitic, containing marine
shells, and sometimes assuming the combination
called orsten, or swine-stone, a sort of coarse
fetid marble. Such is the summit of Mont
Perdu, a calcareous colossus, about twenty miles
in length, and four or five miles in breadth, with
an elevation of 10,500 feet above the level of
the sea.

Sometimes the calcareous beds on the steep
slopes have rolled down, and the broken frag-

* Min. iii. 16.


ments have afterwards been united into bricias,
which are very common in this kind of rock.

In a softer state these beds have been con- Contorted.
volved, in various contrasted forms. " Saussure
cites many examples of these heaps of calcareous
beds, which are contorted in such a manner as
evidently to show that they have been bent by
the effect of the force which parts of the same
beds, in a higher situation, have exerted against

"Among others, he observed this effect in
three different places, on the borders of the lake
of Lucerne. The one near the mouth of the
Reuss : c The bent beds,' says he, e are of a grey
compact limestone ; they rise from the lake in
a vertical position 5 they then bend towards the
south-west, and on that side become concave.
To the north-east, on the side of their convexity,
a hollow presents itself.

( On closely examining these beds, they are
found to be very much broken, and appear to
have been so in the act of bending, and even by
the force that bent them/

" The second place is half a league to the
northward of the preceding, likewise on the bor-
der of the lake of Lucerne, on which Saussure
sailed : it is a mountain called Axenberg. ' From,
the summit to the foot of this calcareous moun-


tain beds are observed in the form of an S, com-
pressed, or of which the bendings are very
strongly marked. These S's are often repeated,
sometimes in contrary directions, and masses of
rocks are found between them, whose stratifi-
cations are not distinct. When these contorted
beds are closely observed, it is found that they
are often broken in the strong curvatures; and
this proves that they were not formed in that

cc The third place is opposite the preceding,
on the other side of the lake : ' It is a mountain
in which the beds, which are nearly horizontal
below, turn up above and form a C, whose con-
cavity looks to the N. N.E. : on the left, or to
the S. S. W. of the C, there is a large hollow ;
and what is most remarkable is, that the beds
which adjoin the lower branch of the C extend
themselves to a great distance, forming a moun-
tain with regular and horizontal beds.'

" From these facts Saussure concludes that
these dislocations of beds are produced by a re-
foulement, or repressure, which has folded them
over each other."*

Calcareous rocks seem to be comparatively
rare in Africa, and even in Asia. As layers of

* Patrin ui. IQ.


flint are found in chalk, so layers of chert, or ke-
ralite, appear in limestone ; while Lydian stone,
and siliceous schistus, sometimes intersect the
primitive calcareous rock.

Limestone often presents mural precipices, as
in the Pyrenees, and sometimes in forms ap-
proaching the artificial, as in the circus, towers,
and cylinder of Marbois. The picturesque ap-
pearances of Chedder cliffs are on a smaller
scale. In the chain of Jura, and in the Py-
renees, calcareous mountains have been ob-
served, with exterior arrects of 40 or 45 degrees,
while the interior become more and more verti-
cal. Palassou and Pasumot, in their descrip-
tions of the Pyrenees, have observed a mountain
of limestone, formed of oval and circular concen-
tric layers, which present a most singular ap-
pearance. On a smaller scale, as in pisolites
and sinapites, limestone often affects the orbi-
cular form.

Saussure informs us, 347, that the chain of
Jura is calcareous, with the exception of some
few spots, covered with calcareous sandstone.
In 1937 he remarks contorted beds of compact
limestone, which he says of course must be sedi-
mental, not crystallised, and must have been
deranged by a refoukment. Nor has the re-


markable intermixture of compact limestone
, with granular, escaped this great observer*.
onThe singular rock which contains pholades,
or sea-dates, is a blackish argillaceous limestone,
rather of a soft consistence f.

primitive. That granular limestone is primitive has been
long allowed. Among many other remarkable
mountains of this stone, the stupendous heights
of Finster Aar Horn, Yungfrau Horn, and
Shreck Horn, or the Peak of Horror, in Swisser-
land, deserve especial commemoration. Saus-
sure has long since observed, that it often pre-
sents lofty spires, like granite; and being a
manifest deposition, must evince that granite
is so likewise. It appears between layers of
mica slate and gneiss, as schistose siderite ; and
alternates with common slate. Primitive lime-
stone is commonly white, dark iron grey, or red-
dish brown, and is not always granular, being
sometimes compact. It sometimes supplies the
place of quartz in mica slate, and sometimes of
felspar in granitoid, and a rock of the gneiss

* Sauss. 2226.

f Id. 1356. On the coast of Aunis, near Rochelle, little oysters
called gryphites are forced into the mud by the sea. The whole
toon becomes a hard stone, and is called the shell-stone of Aunis.
Mem. Acad. deRochelle, tome iii.


structure. It is rarely metalliferous, but in Si-
beria it presents rich mines of copper, and in
South America veins of gold and silver. It is
remarkable, that in limestone the shells retain
their original form, while in clay slate they are
compressed ; a circumstance ascribed to the
great subsidence of the latter. Caverns are sel-
dom found except in limestone, the rock being
commonly eroded by a stream of water.

The Wernerians regard limestone as of three Formations,
formations ; the primary, the transitive> and the
floetz, flat or horizontal. The second often
contains coralites and madrepores; but Faujas
showed a madrepore in Carrara marble, which
is esteemed primitive.

Limestone seldom or never occurs pure, there
being generally a small admixture of argil,
sometimes of silex, sometimes of iron. When
there is manganese it forms a more tenacious


Aspect 1. Common. The characters mostly
correspond with those of marble ; but the mode
of combination must vary, as it is not capable of
so fine a polish.

The colours are white, grey,- black, reddish, and


yellowish. A green tint may be suspected to in-
dicate magnesia.

Granular limestone often belongs to the noble
kinds or marbles; it is also often found more
soft, light, and coarse, when it falls into this di-

Grey granular limestone, with calcareous spar,
from Lusatia.

The same, mixed with slate, from Saxony.

Reddish brown granular limestone, with slate,
from the same.

White granular limestone, from Stiria.

White sparry limestone, in thin shining span-

2&SJ! g les > from China - "There are brought from
China," says Born, " tablets of an oblong square

/ <?

form, often marked with Chinese letters ; of a dull
polish, and sold as artificial, under the name of
rice stones, being regarded as composed of rice
reduced to a paste; but the external characters
and chemical analysis demonstrate that it is only
a sparry limestone, cut in these forms." A like
fabulous idea concerning rice has been entertained
with regard to iconite.

Argillaceous limestone, which naturally splits
into lentiles, convex on both sides, which might
seem to be a bricia were not the paste absolutely
homogenous. Sauss. 1377.


A limestone, containing large shells full of
sand. Sauss. 284.

Aspect 2. Micaceous. Primitive granular lime-
stone is often interspersed with mica, and some-
times with orbicular crystals of quartz. It has
already been observed, that the mere mixture of
mica can never be understood to alter the deno-
mination of the stone.

Micaceous limestone, from the Alps.

The same, from the Grampian mountains, in

The substance called Cipoline marble is often
so coarse as rather to belong to this division.

Limestone, with nodules of mica and of sand,
from the Pyrenees.

A micaceous limestone, in which the mica is so
abundant that the calcareous mixture is scarcely
distinguishable. Sauss. 1 8 1 J .


Texture, compact, generally massive and earthy, character*,
sometimes schistose.

Hardness, from the gypsic to the marmoric.
Fracture, fine scaly, sometimes large and flat
conchoidal, sometimes uneven. Fragments, amor-
phous, rather sharp.

VOL. i. 2 G


Lustre, dull. Opake ; but often translucent on-
the edges.

The most common colour is grey, of various
tints, and yellow of different shades. It is often
veined and spotted in various forms.

Primitive compact limestone, from the Alps.

The same, from the Grampian mountains, Scot-

Primitive limestone, with garnets, from the Py-

Grey compact limestone, intersected with gra-
nular, from the Alps.

Black compact limestone, intersected with chert,
from Derbyshire.

The same, with spots of bitumen. The black
colour often arises from the bitumen, as appears
from the stones becoming white when calcined.

Limestone, of a dull white colour, from Port
Rush, in the north of Ireland. This stone, which
has sometimes been called chalk, supports the
celebrated basaltic columns around the Giants'
Causey. It abounds with jfossile remains, and no-
dules of dark flint: for the depth of sixty feet
under the basaltin it is impregnated in a singular
manner with small particles, mostly oval, of the
basaltin ; and, from the mixture of colour, is vul-
garly called mulatto stone. A most singular ge-
ological fact.


Mr. Kinvan mentions a sky-blue limestone,
from Aberthaw, in Glamorganshire. But this,
like the blue marble of Narbonne, or the blue tur-
quin, appears to be only grey. Dr. Kidd de-
scribes it as light blue, or grey ; and says, that it
is common in Somersetshire, and that it only
occurs in the form of shingle, or large pebbles, on
the sea shore at A bertha w. This colour seems to
indicate a mixture of iron ; and such limestones,
when calcined, become of a buff colour, and fur-
nish a harder mortar than any other.


Many of this description belong to the noble
division, or marbles, not to mention the konites ;
but many also are of a soft and coarse nature,
whence they fall under this Structure. The lime-
stone containing shells is generally grey, but some-
times dull white, or brown. Sometimes even
bones are found in limestone, and in marble ; and
Faujas, as already stated, has recently observed a
remarkable example near Verona, where a fine
black marble, containing petrified bones, is worked
into large columns. Karsten, as quoted by Gme-
lin, has also mentioned a limestone, containing
bones, which is found at Erfurt; but the pieces
seem to be small and detached.


sheiu. To enumerate all the shells contained in lime-

stone .would be infinite ; nor have such as occur
in rocks been hitherto carefully distinguished from
such as are found detached and scattered. It will
be sufficient for the present purpose to mention
such as are generally inherent in large masses of
limestone, konite, or marble ; thus forming, as it
were, a constituent part of these rocks. This
subject will be further illustrated by the plates.

It has been observed as unaccountable, that
the shells of those fish which are called Pelasgic
or Oceanic, as inhabiting the unfathomable depths
of the ocean, are often found at the greatest ele-
vations ; while those which approach the less pro-
found depths, and even the shores, are 'rather
found on the skirts and lower hills. If this ob-
servation be exact, the explication seems very
difficult, except perhaps that, under the chaotic
waters, the proper purity and temperature to sup-
port animal life could only be found at such ele-

The shell venerated as the most ancient, and
unknown in modern conchology, is that called
the Cornu Ammonis, or horn of Jupiter Ammon,
from the twisted horn, a symbol of power in the
images of that deity. In the middle ages they
were supposed to be petrified serpents, and some-
times fraud has cut out heads, being esteemed


pious memorials of the miracles of saints. If they
at all exist at present, they are said to be found
microscopic in the Adriatic sea ; but a contorted
species of nautilus has often been confounded
with Cornu Ammonis. The petrified are styled
Ammonites, the Greek termination in this and
the other shells marking their stony nature. Am-
monites occur of all sizes, from half an inch in
diameter, as those which form the singular Dor-
chester marble, to six feet, or the size of a coach-
wheel, as some have been found immersed and
converted into chalk at Margate.

The nummulites, or porpites, occur in the lime-
stone of Egypt and of France, being thin shells,
or rather movable opercules or covers to protect
some shell-fish. Belemnites *, another embarrass-
ing form, are generally found detached. Entro-
chites, or joints of the sea-star, are very common.
The encrinites, other joints, resemble lilies.

To proceed to the UNIVALVE shells : nautilites
abound in many limestones and marbles; and
sometimes retaining their original lustre, impart

* Perhaps these may be spines of a large pelasgian sea-urchin.
The porpite has at last been observed alive in the South Sea. See
the curious plates to the voyage of Peron, Paris 1808, 4to.; where
the rich and interesting delineations of the zoophytes and mollusk*
are very new and striking.


singular beauty to the opaline marble of Ca-




Buccinite (Trumpet).

Bullite or Globosite.

Turbinite (Screw-shell).



Cochlite (sea-snail).
Among the BIVALVES :

Solenite (Razor-sheath).

Tellinite (Limpet).

Dionite (Venus) Dione.

Aphrodite and Hysterolite.

Chamite (Clam).

Pectenite (Scallop).

Ostracite (Oyster).

Anomite (Gryphite).

Mytelite (Muscle. Mya.).

Pinnite (Naker).

The chief MULTIVALVE shell observed in a
state of petrifaction is Lepadite, or Balanite.

Several crabs, &c. are discovered apart : and a
beautiful little tortoise in flint was found by my
friend Mr. Knight, upon his estate of Milton, in


Cambridgeshire, being, it is believed, an unique

Echinites singularly abound in the chalk-pits of
England, with cockles, &c.; but they are easily
separated, and of course foreign to the present

Limestone, with ammonites, from Dorsetshire.

With belemnites, Thuringia. They may per-
haps have been mistaken for bones.

With orthoceratites, Erfurt.

With nautilites, Upper Austria,

With strombites, Jena.

With cochlites, Norway.

With chamites, Mont Martre.

With gryphites, Alsace.

Numerous other examples might be added.


Zoophytes, including the mollusks, also abound
in common limestone. They are of many varie-
ties; as the turbinated, the porpite, the fungite,
the astroite, c. Among them may also be
classed the milleporite, the celleporite, the entro-
chite, either in many or single joints, and of several
varieties, the gorgonite, the coralite, and the en-
crinite. The trochite is a word used by some for
single joints of the entrochite, which cat* scarcely


be distinguished from those of the encrinite, rarely
marked by the lily at the summit.

Limestone, with nummulites, from Egypt.

With entrochites, Derbyshire.

With madreporites, from Gothland.

Numerous other examples may be added, from
all countries; exclusive of the mere calcareous
petrifactions, which are found slightly adherent
or apart.


This kind is so called from its appearance,
resembling conglomerated peas; and is chiefly
brought from Carlsbad in Bohemia, where it con-
stitutes a large bed. It is of a yellowish white ;
and the imaginary peas are in elegant concentric
layers of white and brown, formed around a grain
of sand, like pearls in the shell. Cronstedt has
with some propriety ranked it among the sinters
or depositions.


In this the orbicular accretions are smaller
than in the former; the structure quite distinct,
and more compact. The name is derived from
mustard seed. Some call it meconite, from the
seed of the poppy; while others use the term


oolite, from the eggs or roe of fish : but as this ap-
pellation might imply that the grains equal the
eggs of birds, it is ambiguous ; not to add that,
as the substance was really supposed to be the
petrified roes of fish, whence the English roe-
stone, it is better to dismiss a term leading to erro-
neous ideas. The analogy between pisolite and
sinapite is also preferable, both being derived from
the vegetable kingdom.

This substance is far more abundant than piso-
lite. According to Gmelin, it is frequent in the
stratified mountains of Gothland, Saxony, Thu-
ringia, Brunswick, France, Swisserland; forming
ample and often repeated strata, of a dull grey or
brown colour ; and sometimes, though rarely, pre-
senting animal remains.

The Ketton stone of Rutlandshire is a fine ex-
ample of this kind of rock.

Sinapite!, from Iceland.

The same, from Ketton.

The same, of a still finer grain, from Bath.

The same, from the various countries mentioned
by Gmelin, where, as it forms vast beds, it cannot
be classed among the depositions.



Ancient. The substances called alabastrum and ala-
bastrites by the ancients, are well known to be
merely calcareous, as they effervesce with ni-
trous acid ; whereas the moderns have applied
the name of alabaster to quite a distinct sub-
stance, impregnated with the sulphuric acid, so
that the nitrous can produce no effect.

The classical writers of antiquity more fre-
quently use the word alabastrites than ala-
bastrum ; and it seems therefore far more proper
to retain the former name for the ancient ala-
baster, than to apply it with some writers to the
modern. In general it is distinguished by its
yellow colour, especially mentioned by Pliny;
and often by brown stripes, arising from suc-
cessive depositions, with some resemblance of
the layers of the onyx, whence the onyx tables
and pavements of the ancients. For alabastrite
is acknowledged to be a mere deposition from
superincumbent rocks of marble ; and, with sta-
lactite and stalagmite, forms the sinter of the
Germans; while alabaster is an original rock,
and is even found primitive in the Alps.
Of this remarkable substance, so well known


in Roman luxury, Pliny gives the following ac-
count. " Our ancestors thought that onyx was
only produced in the mountains of Arabia, and
in no other region ; but Sudines adds Carmania*.
At first only drinking vessels were made of it;
but afterwards the feet of beds, and even seats.
Cornelius Nepos says that it was reputed a great
wonder when P. Lentulus Spinter displayed am-
phora? of onyx as large as Chian casks ; yet five
years after he saw columns thirty- two feet in
length. But from more refinement in the choice
of this stone, four columns of a middling size,
placed by Cornelius Balbus in his theatre, were
esteemed monuments of surprising grandeur.
We have seen more than thirty in the dining-
hall which Callistus, well known by his power
among the freemen of the emperor Claudius,
had erected at great expense.

" Some have called this stone alabastrite ; and
of it little pots or boxes for ointments are formed,
as in them it is supposed to be less liable to cor-
rupt f. When calcined it is also used for plas-

* So Brotier's edition: some read Germany.

f Hence the name, which implies what cannot be taken hold
of; because, as commonly supposed, these little pots had no han-
dles. But may it not imply the slippery smoothness of the pot or

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