MARBLE, a variety of lime-stone, of so compact a texture as to adndt of a beautiful polish. The difrerent kinds of marble are infinite, therefore any attempt to describe them in detail would necessarily occupy inueh nnire space than we can allow to this article : they all agree in being opaque, excepting the white, which becomes transparent when cut into thin pieces. In the Borghese palace, at Rome. are som9 specimens of marble exquisitely- white. so flexible, that if poised horizontally on any resisting body placed on a plane, a salient curve will be 'brined by the two ends touching the plane. A similar property is aequired in a small degree by statuary marbles exposed to the action of the sun. which no doubt weakens the adhesion of the part ieles. It is this which frequently occasions the exfoliation of projecting r•ts. and the artist would do well to ascertain, by experiments, the kind of marble, that has the least tendency to this desiccation.
Tile greater part of the quarries. which supplied the ancients with marble. are entirely unknown ; in the Napoleon ALI:scum are preserved the most exquisite specimens of many of them, the grand repositories of which are consigned to oblivion, unless chance should guide sonic penetrating eye to their dark recesses.
Da Costa, in his " Natural History of Fossils," gives a large catalogue of marbles, disposed in a methodical order, which we shall follow in the following brief notices of this extensive subject : Division I.—Marbles of one plain colour.
Section 1.—Black marbles. Most of these contain bitu men, and are fetid when bruised.
Eramples.—The Namur Marble, the marble of Ashfiird in Derbyshire, Dent in Yorkshire, near Criekhowell,Tenby, Kilkenny, &c. The marble, anciently called Marmor Locul h2um, and now Nero Antico, Section 2.—W hi tla rb I es-.
Examples.—The marlde of Poros, in which the Laocoon and Antinous are executed ; the Carrara marble, of finer grain, much used in modern sculpture ; the Skye marble, noticed by Dr. MaeCulloch; that of Inverary, Assyut, Blair Athol, &c.
&Men 3.—Ash and gray marbles.
Era mrles.—A beautiful marble, of compact oolitic tex ture, at Orelton, near the Clee Hills, in Shropshire, deserves mention.
Section 4.—Brown and red marbles.
E.c«mples.—The Russo Antico, a rival to which, at least in colour, has been !build on the estate of the Duke of Devonshire, near Buxton. The mottled brown marble of
Beetham Fell, near Miluthorp, is of good quality.
Section 5.—Yellow marbles.
Example.—The Giallo Antico. Siena marble, also dug at Marra, near Lisbon, That used in ancient llornd is said to be from Numidia.
Section 6.—Blue marbles.
Examp/e.—Near St. Pons, in Languedoc.
Section 7.—Green marbles.
Eranyle.—The Marmor Lacedmonicurn of Pliny. It is Slug near Verona.
Division H.—Marbles of two colours.
Section 1.—Black marbles, variegated with other colours.
Example.—Near Ashburton, in Devonshire ; Torbay, in the same county ; Bianco, or Nero Antico, the African Breccia of the ancients ; Giallo e Nero Antico.
Section 2.—.White marbles, variegated with other colours.
Example.—Marble imported from Italy. Marbles of this general character occur in Siberia ; at Plymouth ; at Killar ney; in Sweden, &e.
Section 3.—Ash and gray marble, variegated with other colours. These are very numerous, and occur in various parts of Europe.
Section 4.—Brown and red marbles, variegated with other colours.
Section 5.—Yellow marbles, variegated with other colours. Section 6.—Green marbles, variegated with other colours. Erample.—Djyptian marbles. The Marmor Tiberium and Angusture of Pliny ; some Verde Antico, as that dug near Susa, in Piedmont ; the beautiful marble of Anglesey (called Mona marble): the marble of Eohnerden, in Sweden. Division III.—Marbles cariegated with many colours. Example. —Some orthe Plymouth marble ; the beautiful 'orocatello, or brocade marble, of Italy and Spain.
Marbles containing shells, corals, and other extraneous bodies.
In this division of marbles, the British islands are rich. Some of the Plymouth, Ashburton, and other Devonian limestones, are extremely beautiful, from the abundance of fine corals exquisitely preserved in them ; the crinoidal marbles of Plintshire, Derbyshire, and Garsdale in Yorkshire, are elegant examples of the carboniferous limestone; the shell marbles of Ranee, Northamptonshire, Buckingham, Whiehwood Forest, Stamford, Yeovil, may be noticed from the oolitic rocks; that of Petworth and Purbeck, from the Wealdon strata, has been extensively used by the architects of the middle ages. In general, the working of the English marbles is costly, and their use limited.