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it to this mode, though Wallerius would perhaps
have called it a tufaceous limestone.



* Breislak, ii. 26 1. At Bionnay there are houses built of a cal-
careous tufa, containing fragments of lime-spar, limestone, and
slate; the base being of a lively brick red colour, and strongly effer-
vescent with acids. Sauss. 752.



I MODE XIII. CALCAREOUS INTRITE. 519

STRUCTURE III. TUBULAR.

From the tower, or ancient pharos, at Dover
Castle.

The same, from the banks of the Tees, and
other rivers in the north of England.

The same, encrustrating various objects, as
birds' nests, plants, leaves, &c.



MODE XIII. CALCAREOUS INTRITE.

This mode is rare, and of little consequence,
especially as the stones are not remarkable for
beauty, and seldom used in the arts.

The most singular, is what Werner would call Porphyritic,
a limestone porphyry ; being a compact lime-
stone of a reddish white colour, sprinkled with
minute crystals of white felspar. It was disco-
vered by Gillet Laumont, in the mountain called
Bonhomme, in the Alps.

Another calcareous intrite is a fine grained Marble of

, _ . Nonette,

limestone, with angular spots of calcareous spar,
something resembling a porphyry. It is of a
yellowish white colour ; and bears the name of
marble of Nonette, from a place situate at the
confluence of the rivers Alagnon and Allier, in
the department of Puy-de-Dome. There is also



DOMAIN V. CALCAREOUS.



a conchitic marble found near the same place ;
but the former being more easily worked, is
preferred for chimney-pieces and other objects,
according to the information given me by M.
Lucas, a most obliging and intelligent youth,
who has published some useful works on mine-
ralogy. The father has the care of the collection
of the Jar din des plantes s and by his respectable
character, and gentle manners, prevented many
outrages that were offered to that sacred deposit,
during the times of anarchy,



MODE XIV. CALCAREOUS GLUTENITE,

This mode presents many important objects^
as the celebrated bricias and kollanites in mar-
ble, with the calcareous sandstones, used for
various purposes of construction. It falls, as
usual, under two divisions, the large grained and
the small,

STRUCTURE J. LARGE GRAINED,

Bricias of limestone are common at the bottom
of many calcareous hills, but attract little atten-
tion ; except in colour and grain, they belong to
that noble mode called marble. A singular kind,



MODE XIV. CALCAREOUS GLUTENITE.

described by Saussure, may suffice. He observed
it at the Col de la Seigne, near the mountain
of Bonhomme.

" On this road we find a quantity of fragments
of a very singular calcareous bricia ; and conti-
nuing to ascend, we leave on the right, above the
path, the rocks from which these fragments are
detached. The same bricias are again found in
the same situation, on the opposite slope of the
Col de la Seigne, and in the White Alley : but I
shall describe them here, that I may not return to
them. The paste of these bricias is sometimes
white, sometimes grey ; and the fragments which
it contains, are some white, some grey, others
brownish red, and almost always of a different
colour from the paste which unites them. They
are all of a calcareous nature, at least such were
all those that I could see ; and it is remarkable
that they have all a lenticular form very much
flattened, and that they are all placed in the
direction of the plates of the rock : one would
say, on seeing them, that they had all been com-
pressed and bruised in the same direction. This
same stone is mixed with mica, especially in the
interstices of the layers, and between the frag-
ments and the paste which unites them ; but no
mica is observed in the fragments themselves.



522 DOMAIN V. CALCAREOUS.

Jnfiltrations of quartz are also found in these bri-
cias. This rock is cut by frequent fissures, per-
pendicular to the planes of the beds. It is palpa-
bly seen, that these clefts have been formed by the
unequal subsidence of the beds, and not by a
spontaneous retreat : for the pieces, or foreign
fragments, are all divided, and distinctly cut by
these fissures ; while in the natural divisions of the
beds, these same fragments are entire, and pro-
jecting from the surface. The nodules of quartz,
and the several crystals which schisti contain,
present the same phenomenon ; and the same con-
sequence may be drawn from it ; they are divided
in the clefts, and whole in the separations of the
layers.

" Although these flattened fragments, as I hav$
said, afford, at first sight, the idea of compression,
yet I cannot admit it; no other vestige of this
compression being observable : I should rather
imagine that these fragments have belonged to
, very thin layers, which have been rounded under

the waters, by rolling and friction ; that afterwards,
when they have been successively carried down
and lodged by the waters, they have taken the
horizontal position that their weight imposed on
them; and that afterwards the elements of the
calcareous stone which forms the base of the



MODE XIV. CALCAREOUS GLUTENITE. 523

bricia, and which was deposited at the same time,
or alternately with them, have enclosed and kept
them in that position."*

The nagelfluh of the Swiss is a bricia, with a
calcareous cement; the fragments seem to be
commonly siliceous ; but Mr. Jameson says that a
kind, wholly calcareous, is found in Bavaria; itis
incapable of polish.

It is singular that no bricia can be clearly and
positively assigned to the times of ancient art.
Ferber informs us, that the Italians apply the
word bricia to any marble, which has spots that
are clear and distinct ; while it ought to be con-
fined to real bricias, consisting of fragments joined
by a calcareous cement.

The bricia which seems to have the best claim African bricia.
to antiquity, is that called the African, which, on
a black ground, presents large fragments of a
whitish grey, of a deep red, or of a dull purple.
Of this marble there is a large column in the
Napoleon museum ; but the name of African
seems to have been bestowed merely on account of
its black ground ; for it is not mentioned by any
ancient author, and, if known to antiquity, was
probably Grecian ; perhaps the Chian, with spots
of many colours on a black ground. As the walls



841



DOMAIN V. CALCAREOUS.



of their city were built with this marble, the ques-
tion might perhaps still be settled by a learned
traveller. When they showed them in a boasting
manner to Cicero, his dry sarcasm, on their great
pride and small domain, was, " I should have ad-
mired them more, if they had been built of tra-
vertine." After all, this marble may perhaps be
Italian ; for Ferber informs us that the same kind
is still found at Seravezza, on the opposite side of
the mountain to Carrara, which is also called
Africano, and employed instead of the antique*.
The names, imposed by the ignorant and interest-
ed dealers and artists, deserve no credit ; and an
intelligent traveller must study the marbles in the
undoubted remains of antiquity, beginning with
those which continued in general estimation and
use for many centuries, as the Laconian, the
Phrygian, the Numidian, and the imperial or
Egyptian.

No other bricia appears in Ferber's catalogue of
Antique, the ancient marbles of Rome ; but some others
are styled antique, probably only on account of
their beauty. Such are the rose bricia, which, on
a base of bright red, is enriched with little spots,
rose and black, with larger ones of a beautiful

* Da Costa, p. 211, positively informs us that the black marble
with red and white spots, is Italian, though called African.



MODE XIV. CALCAREOUS GLUTENITI!.



525



white ; that called arlequino, which on a pale yel-
low, presents many fragments of various colours,
resembling the beautiful bricia of Aix, but with
more splendour ; the chocolate brown, with little
angular fragments of white ; and the white with
red fragments. What is called the grand antique,
is composed of large fragments of black in a white
cement*. The French apply the name, violet, to Violet.
a bricia, which, on a ground of pale brown, pre-
sents fragments of lilac and of white. One of the
violet bricias, described by Brard, is of a yellowish
green; and presents white, green, violet, red, and
orange spots : but our author does not seem care-
fully to distinguish between Italian bricias, which
are often merely spotted, and the real bricias,
which are composed of fragments.

Among the bricias of modern Italy, may be Modern,
mentioned what the French also call violet-bricia,
being merely of a reddish brown, with white veins;
that of Brentonico with large yellow, grey, and Italy.
rose spots ; that of Bergamo, of black and grey in
a greenish cement ; and that of Alcamo, in Sicily,
of a bright grey with rose spots. The territories
of Verona and Trent yield a beautiful bricia of
pale red, crimson, and bluish fragments in a red
cement Spain boasts the bricia of Riela, in Ar- Spain.



Brard, 340.




DOMAIN v. CALCAREOUS.



ragon, of a reddish yellow with fragments of
black ; and those of Valencia, of a pale yellow.
That of Old Castile is much employed at Paris,
being of a bright red, dotted with yellow and
black, and enclosing fragments of a pale yellow,
brick red, deep brown, and blackish grey*. They
are rather round, so that it might be called a
pudding-stone, if this division were natural; for
in the original and beautiful pudding-stone of
England, whose name has passed into all lan-
guages, the small pebbles are often angular,
which, with many other instances, shows the divi-
sion is unnecessary.

No bricia worth mention, seems hitherto to
have been discovered in the British dominions.
Prance. France presents a beautiful marble of this de-
SCI *ipti n ) ver j common at Paris. The ground is,
in some pieces, of a pale brownish red, in others
of a straw colour ; and is itself chiefly composed
of very small fragments of the same colours with
the larger, which are of all shapes, and from half
an inch to two or three inches in size. These
spots are generally of a light brown, or straw
colour, and are interspersed with other fragments
of a slate blue and pale red, with others of a light



* The celebrated Irocatello, or cloth of gold of Catalonia, is by
Tsome regarded as a bricia*






MODE XIV. CALCAREOUS GLUTEN ITE. 527

grey and dull white : a striking singularity is, that
the large brown spots have sometimes red edges >
and an oval or triangular spot of light grey will
have a red spot of the same shape in the centre ;
so that the very fragments would seem to be of
original crystallisation, which has been modified,
or rather disturbed, by some violent cause, at a
particular period of its progress. This singular
marble might, with the English kollanite, form
a cabinet of study for the geologist; for the
appearance of both is utterly irreconcileable with
received opinions. As sand is now allowed to be
often a product of original crystallisation, so peb-
bles, which are only a larger sand, must in the
kollanite, and may in this calcareous rock, be of
original formation, and afterwards agglutinated
by a resumed progress of the process.

This singular bricia is at Paris called brchc
cTAleppe, as if it came from Aleppo in Syria ; but
M. Brongniart informs us that this is a corrup-
tion, and that it should be called cCAlet, from a
place about a league from Aix ; yet he describes
it as red, black, and grey, which must be quite a
different sort. Brard, who has treated the French
marbles with great care, says, that the bricia
sometimes called of Aleppo, and sometimes of
Alet, by the marble-cutters of Paris, is the antique
violet bricia, which has been already mentioned;



DOMAIN V. CALCAREOUS.

but none of his descriptions in the least correspond
with that under view* * and it is with regret that
on this and many other occasions, the praise of
accuracy, though it ought to form the chief ambi-
tion of such a work, must be withheld. It is also
surprising that he did not learn, from Brongniart,
that the bricia of Aix, which he compares with
the Arlequino, must be the same with that of Alet
in the vicinity of that town. His description of
Of Aix. the bricia of Aix, in fact, corresponds with the
present, as presenting grey, brown, and red spots,
on a yellowish base. The same remark may ex-
tend to his bricia of Marseilles, which is reddish,
with white, grey, and brown fragments ; and which,
he adds, is much used and highly esteemed at
Paris ; where it is unaccountably called bricia of
Memphis. It is surprising that Saussure, who
has described Aix and its vicinity, has not indi-
cated this singular marble, which was so worthy
of his attention in every point of view.
Of Eygiier*. Another singular French marble is the pudding-
stone of Eygliers above Mont Dauphin, on the
right bank of the river Guyl. This is composed
of pebbles chiefly white, grey, and yellow, joined
by a reddish cement, and receives the finest polish.
Beautiful tables of this marble may be seen at

P. 341.



MODE XIV. CALCAREOUS GLUTENITE, $

Grenoble; and inspection must verify whether the
pebbles have been rounded by friction, or the
whole be an original rock of a particular crystal-
lisation.

Another marble, called a violet bricia by the others,
French, comes from Seix and other places in the
department of Arriege, which is particularly rich
in beautiful marbles. It is a coarse brown, spot-
ted with lilac and white. That of St. Romaine, in
the department of Cote d'Or, so styled from the
excellent wines of Burgundy, is of a brick red
with angular fragments of yellow. Doulers, in
the department of the North, presents a bricia of
many fragments, ash colour, white, and reddish.
That styled of the Pyrenees, is of a brownish red,
with black, grey, and red fragments, and has con-
siderable reputation.

Of the common kind, Saussure has observed
the following examples :

The mountain near Vevey is composed of coarse
pudding-stone, the rounded flints being united by
sand, and this sand by a calcareous gluten, which,
in the rents and intervals of the beds, assumes the
form of spar.

The pudding-stone of which Mount Rigi is
composed, consists chiefly of red clay pebbles, so
soft as to be affected by rain water, and united by
a calcareous gluten.

VOL. i. 2 M



DOMAIN V. CALCAREOUS.



A pudding-stone of fragments of black horn-
stein in a gluten of clay, iron, and lime*.

The chief specimens have been already indi-
cated.

STRUCTURE II. SMALL GRAINED.

Calcareous sandstones are regarded as common.
That of Fontainebleau, which is commonly rec-
koned calcareous, does not, by Brongniart's ac-
count, always effervesce with the nitrous acid ;
but only that of two quarries, Bellecroix and Ne-
mours, in which the curious crystals are found.
The others afford siliceous sandstone.

The sandstones which present zones of different
colours, and dendritic delineations, seem to be
chiefly argillaceous, the clay cement being im-
pregnated with iron. Calcareous sandstone often
alternates with limestone, and is ascribed by many
Sites. to the same formation. It is the most common of
all the sandstones, and forms long chains of hills,
from Osnabruck down to Hessia, and along the
Rhine. It also constitutes the base of the Can-
ton of Berne, and rises into considerable moun-
tains in the south of France, particularly that of
Caume, on the north of Toulon, which consists

* 1099* 1941* 1539.



MODE XIV. CALCAREOUS GLUTENITE.

of alternate beds of limestone and calcareous
sandstone*.

According to Patrin, the sandstone of Fontaine- Of Fontaine

bleau.

bleau is always a calcareous glutenite ; but when
he praises its utility at Paris, where it is employed
in paving the streets, he forgets that it wears out
in three years ; while granite might be had from
Cherbourg, which would last thirty. This cele-
brated sandstone sometimes forms regular beds,
and sometimes only appears in blocks, dispersed
in heaps of pure quartzy sand, upon which the
gluten does not seem to have acted. For Rome
de Lisle has long since remarked, that such sand
is often a pure homogenous production of nature,
which must not be confounded with those pro-
ceeding from decomposition^. The formation of
this stone seems illustrated by the noted crystals,
which, though composed of quartzose sand, as-
sume the rhomboidal form of calcareous spar;
and some even present crystals of a beautiful yel-
low spar, quite transparent. Perhaps it was in a
different quarry, that Lassone made the singular
remark, that the new surface, at the end of some

* Patrin, iii. 324. He seems singular in his opinion that the
building stone used at Paris is a calcareous sandstone, while all
others regard it as a konite. See Brongniart, art. Moellon, i. 204.
It is the chaux carlonatte grassier e of Hauy.

t ii- 63.

2 M 2



532 DOMAIN V. CALCAREOUS.

months, was covered with a glassy crust of a sili-
ceous nature, arising from some lapideous juice,
which remains, as before observed, among the
secrets of nature ; because stones have never been
analysed in their original state.

Even Mr. Kirwan has little enlarged upon the
calcareous sandstones. Mr. Jameson has, as
usual, employed much labour in illustrating the
different formations ; but he has not drawn a pre-
cise line of distinction between the different kinds ;
as it is probable, however, that his third forma-
tion is chiefly a calcareous glutenite, the following
curious observations well deserve a place here.
in columns. " No rock presents a greater variety of exter-
nal appearance than this sandstone. Its valleys
are deep, rocky, and romantic ; its hills conical,
steep, and cliffy ; and it often presents grand co-
lossal pillars and masses, which, from their num-
ber and variety of their shape, form most striking
rocky scenes. These hills, pillars,. and masses,
often reach a considerable height ; but their sum-
mits are all nearly on the same level. One of the
most striking appearances of this kind is at Aders-
bach, in Bohemia. There we observe numberless
cones, pyramid s, and pillars, sometimes isolated,
sometimes joined together, and from two to three
hundred feet high, spreading over a considerable
tract of country. In other places, caverns or



MODE XIV. CALCAREOUS GLUTENITE.

grottos appear, from which there issue many
streams, that give rise to waterfalls, and thus in-
crease the beauty of this striking scene. These
caverns are wide at the mouth, but become very
narrow towards their further extremity, and are
generally very short. This form shows that they
owe their existence to external agents, particularly
water. A more near examination discovers that
the seams of the strata of the different isolated
masses correspond to each other ; which renders
it probable that all these cones, pyramids, and
pillars, have been formerly united; and that the
perpendicular rents or fissures have given rise to
this disunion, which has been afterwards increased
by the action of the air, and by the water carrying
away the softer or more loosely aggregated parts
of the sandstone, and leaving the harder parts in
these various forms. A similar appearance of
sandstone occurs near Tunis, and, from its striking
resemblance to ruins, is described as the remains
of a great city, by some travellers who saw it at a
distance. In the land of the Namaquas, in
southern Africa, and on the banks of the Wolga,
there are similar appearances."* This glutenite
may, however, be argillaceous.



* Geognosy, i6l. Soulavie, tome i. gives a print of square caU
careous columns at Ruons, on the river Ardeche.



DOMAIN V. CALCAREOUS.

In his edition of Linnaeus, Gmelin has produced
various minute substances, while he ought to have
begun this genus with his sixteenth species, as the
most important, being the Suadrum, celebrated as
he says in architecture*. The venerable Wal-
lerius has with more judgement, as usual, de-
- scribed the quadrum; so called, as he says, be-
cause it often rises in square forms. He esta-
blishes its calcareous nature ; and says that it is
of great use in architecture. He mentions the
white, the yellow, the grey, and the red, the latter
being from Shropshire. Pott, Vogel, and others,
at first supposed this stone to be merely cal-
careous, and even the sand may in fact be cal-
careous; but in general, upon leaving a small
fragment in the nitrous acid, the quartzy sand will
become visible or tangible. A useful observa-
tion is, that the nearer to the sea it is quarried,
the less it will withstand the weather; as any
saline particles attract the humidity, which during
frost expands and splits the stone. In like manner
if konite be accidentally moistened with sea-water,
it will be subject to decay.

In the passage of Fours, near the mountain of

* He ranks it among the calcareous, though by his description it
must be argillaceous. The cement is, however, sometimes of marl,
or a mixture of lime and clay.



MODE XIV. CALCAREOUS GLUT^NITE.

Bonhomme, Saussure observed a remarkable sand-
stone, which he thus describes :

"All the beds of sandstone observed on this OfFonr*.
mountain do not contain rolled pebbles ; there
being irregular alternations of beds of pure sand-
stone, and beds mixed with pebbles. The most
elevated contain none. The highest of those
which contain any, is a continued bed of a foot in
thickness, and which rises 30 degrees to the
N. W.

" Some of these beds, filled with pebbles, pre-
sent a very remarkable singularity : on their ex~
ternal surface exposed to the air, is observed a
kind of network formed of black and saliant veins,
two or three inches above the surface of the rock ;
the meshes of this net are sometimes irregular;
but for the most part they are oblique-angled
quadrilaterals, whose sides are eight or ten inches
long. As these rocks have all a tendency to split
in rhomboids, it seems that there have been for-
merly clefts, which divided the beds in parts of
this form ; and that these clefts have been filled
by sand, which has been cemented by a fer-
ruginous juice : this solid gluten has made these
parts harder than the rest of the rock ; and when
the injuries of the air have attacked the surface of
these beds, the meshes of the net have remained
protuberant.



536 DOMAIN V. CALCAREOUS.

" The rounded pebbles, which have been long
exposed to the air, have also outwardly assumed a
blackish ferruginous tint ; but those which are still
enclosed in the beds of sandstone have, like that,
a yellowish colour. I found none in it which
were not of a primitive nature ; and the most part
were of a very hard grey or reddish felspar, and
confusedly crystallised. They are then stones
which do not naturally possess a rounded form,
and which consequently only receive that they
have here, by rolling and the friction of the
waters.

" All these sandstones effervesce with acids ;
but the ferruginous parts of the net much less

than the base itself. In like manner, if the sand-

.
Stones which contain pebbles, and those which do

not, are compared, in the former will be found
more calcareous gluten, their coherence being
much more diminished by acids. On the very
summit of the mountain these sandstones are co-
vered by a grey shining slate, which exfoliates in
.the air; and descending from this same summit,
on the N. E., on the opposite side to the passage
of Fours, beds of sandstone will be observed ex-
actly similar, and which there divide of themselves
in small parallelepiped fragments."*



780.



MODE XIV. CALCAREOUS GLUTENITE. 537

Saussure also gives numerous other examples of
calcareous sandstones.

Near Vaucluse, 1545, are beds of sandstone, OfVauciuse.
composed of angular and round fragments of
transparent white quartz, and of yellowish or
greenish steatite, semitransparent, in a calcareous
gluten.

A sandstone, 1564, of a red wine colour, in-
clining to violet, very fine, and spangled with cal-
careous spar. It makes a warm effervescence
with the nitrous acid, leaving a sand of white
quartz, and some grains of felspar.

A sandstone, 1 487, composed of grains of
quartz, and a kind of red ochre, in a calcareous
cement.

The sandstone of Voisy, 304, consists of
quartzy sand, mingled with a little clay, and
small specks of mica, all united by a calcareous
gluten, which sometimes assumes the form of
spar in the interstices of the beds.

" I have seen myself," says this accurate Recent

formation.

author, 305, " on the shores of the Mediter-



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