Marble slab

“ Marble wall-slabbing needs very careful fixing, and should be well supported by a sufficient number of cramps at a little distance from the wall, leaving a space of about half an inch at the back of the slab. ”

“ A sheet of glass or of marble we usually regard as a thing that may break but does not bend. But all of us have seen glass strips, if they are long enough, bend under their own weight; and there are even marble mantelpieces which, if examined, show that the slab of marble has bent. Thus we can readily imagine that sometimes the strata of the earth will bend by reason of the weight put upon them. If that weight is not put on them quite evenly the strata will be still more likely to bend; it will go from bending to buckling, and from buckling to breaking. ”

“ In preparing them 20 pounds are always ground at once. The color is ground upon a large marble slab with water and gall, to mineral colors the necessary glutinous matter is added and this is formed to a thick paste and then ground in the color-mill. ”

“ Owing to this method of building the progress of the work from day to day can often be traced by a change in the look of the concrete. About 3 ft. appears to have been the average amount of wall raised in a day.
Marble linings were fixed very firmly to the walls with long clamps of metal, hooked at the end so as to hold in a hole made in the marble slab. Fig. 4 gives an example, of the time of Marble Augustus, fixed against a stone wall. The blocks were usually marked in the quarry with a number, and often Marble linings, &c. ”

“ A thin facing of marble or other ornamental solid or even plastic material may be applied to the face of the slabs during the process of casting, thus enabling the work to be finished as it is carried up, or a key may be formed on the face of the slab to enable the structure to be plastered afterward. ”

“ Generally the ground for this is stone-colour, and the materials are the same as for the black and gold marble—i.e. black and white in oil-colour.
Spread over the slab or mantelpiece a thin and carelessly mixed blending of the black, white, and medium, so that when it is covered the ground shines generally through that scumbly coating with portions all irregular; then take a long studying look at your work, and with your sash-tool put in the dark grey portions loosely, leaving the covered ground for the light as you might if painting a picture; rub in your larger masses roughly ”

“ When set, the slabs so formed were attached to the wall with cement. The large marble slabs are one to two inches thick, and, besides the cement, are fastened to the walls by iron [? bronze] clamps. The pavements of ground floor and gynaeceum are of white marble with dark gray stripes. [Proconnesian.] In the south-east angle of the square area under the dome is a square of marble mosaic, of which details are given in Salzenberg’s Plate xxii., Figs. ”

“ In this form the marble is used for facing the walls of buildings upon a back of brick, giving all the effect of a solid wall of marble at much reduced cost. In the most expensive structures only are the walls built of solid blocks of marble or freestone. Marble slabs for mantels and other interior work are sawed like those for building, and are then rubbed smooth upon a heavy revolving table of cast iron, called the rubbing bed, and afterward polished.—According to the census of 1870, there were 22 marble quarries in operation in the United States, employing a capital of $1,316,600. ”

“ The outside walls shall be faced with slabs or blocks of marble or granite, not less than two feel thick, and fastened together with clamps securely sunk therein,–they shall be carried up flush from the recess of one foot formed at the first floor where the foundation outside wall is reduced to two feet: The floors and landings as well as the roof shall be covered with marble slabs, securely laid in mortar; the slabs on the roof to be twice as thick as those on the floors. ”

“ In those which have been standing for a century it is, save in exceptionally sheltered positions, so far advanced that a very slight pressure suffices to crumble the stone into powder. But with this internal disintegration we have to take into consideration the third phase of weathering to which I have alluded. In the upright marble slabs it is the union of the two kinds of decay which leads to so rapid an effacement of the monuments. ”

“ The walls and arched roof are as smooth and polished as if they had been wrought by art, and are composed of a fine glittering red and white granite, supported at intervals by columns of a deep blood-red shining porphyry, which, by the reflection of the lights, presents an appearance inconceivably grand. At the extremity of this passage is a sloping wall, formed of a single mass of purple marble, studded with sprigs of rock crystal, which, from the glow of the purple behind, appear like a continued range of amethysts. ”

“ Cast your eye downwards, and let it range over the immense masses of chiselled rocks, wrought into regular shape, enriched with architectural device, and piled on each other till the senses are pained in endeavoring to take in the colossal fabric of more than seven hundred feet in height; glance at the huge mouldings into which the wall swells at its termination; mark the high colonnades of pure showy marble, that are ranged along the edge of this mighty structure; see within this the marble tesselated pavement, ascending by flights of steps, and encircling the mountain ”

“ Marble, from its costliness, and the difficulty of working it, is seldom, if ever, used in solid pieces in buildings; thin facings of it are set upon stone backings, much as rare woods are used in veneering by the cabinet-maker. The marble is sawn into thin slabs, like other stone, and the face is polished by rubbing on it the surface of another piece, fine sand, mixed up with water, being used to cause abrasion. ”

“ We saw quantities of small pieces of various sorts of granite, and porphyry scattered over the plain, which had been carried down by a torrent, probably from quarries of ancient ages; these were white, mixed with black spots; red, with green veins, and black spots. After this, all the mountains on the right hand were of red marble in prodigious abundance, but of no great beauty. They continued, as the granite did, for several miles along the road, while the opposite side was all of dead-green, supposed serpentine marble. ”

“ If you build in marble you must either carve it into joyous decoration, like the lives of dancing children that adorn the marble castles of the Loire, or fill it with beautiful sculpture, frieze and pediment, as the Greeks did, or inlay it with other coloured marbles as they did in Venice. Otherwise you had better build in simple red brick as your Puritan fathers, with no pretence and with some beauty. Do not treat your marble as if it was ordinary stone and build a house of mere blocks of it. ”

“ We stand on the banks beside fluted columns of snow-white marble, and see broken marble everywhere near. That man who ploughs on the southern ridge of the sand turns up marble bits at every step of his bullocks, and the girls behind him, who are planting, uncover stones from the temple at almost every stroke of their hoes. ”

“ For not only are whole walls now covered with marble, but the marble itself is carved out or marqueted so as to represent objects and animals of various kinds. No longer now are we satisfied with formal compartitions of marble, or with slabs extended like so many mountains in our chambers, but we must begin to paint the very stone itself! ”

“ Now, on the wall, these pieces are mere flat slabs cut to the arch outline; but under the soffit of the arch the marble mail is curved, often cut singularly thin, like bent tiles, and fitted together so that the pieces would sustain each other even without rivets. It is of course desirable that this thin sub-arch of marble should project enough to sustain the facing of the wall; and the reader will see, in Fig. LVII., that its edge forms a kind of narrow band round the arch (b) , a band which the least enrichment would render a valuable decorative feature. ”

“ Terminal figures, columns of marble or granite porticos, arches, are seen in the vistas of the wood-paths, either veritable relics of antiquity, or with so exquisite a touch of artful ruin on them that they are better than if really antique. At all events, grass grows on the tops of the shattered pillars, and weeds and flowers root themselves in the chinks of the massive arches and fronts of temples, and clamber at large over their pediments, as if this were the thousandth summer since their winged seeds alighted there. ”

“ At the beginning of the century, delicate shafts of marble, highly polished, were employed rather freely, but as these seldom carried weight, and were mainly ornamental in character, they were gradually eliminated, yet, without sacrificing any of the beauty of structure since combinations of light and shade were secured by the composition of various forms, and the use of delicately rounded mouldings alternated with hollows, so as to produce forcible effects in high light and deep shadow. ”

“ The floor of it is of rich mosaic, encompassed by a low seat of red marble, and its walls are of alabaster, but worn and shattered, and darkly stained with age, almost a ruin,—in places the slabs of marble have fallen away altogether, and the rugged brickwork is seen through the rents, but all beautiful; the ravaging fissures fretting their way among the islands and channelled zones of the alabaster, and the time-stains on its translucent masses darkened into fields of rich golden brown, like the color of seaweed when the sun strikes on it through deep sea. ”

“ Most of the coloured or variegated crystalline marbles have originated in this manner. Often bands of calc-silicate rock alternate with bands of marble, and they may be folded or bent; in other cases, nodules and patches of silicates occur in a matrix of pure marble. Earth movements may shatter the rocks, producing fissures afterwards filled with veins of calcite ”

“ Where, on the other hand, marble is abundant and good, refinement is to be met with, for no other building material exists in which very delicate mouldings or very slight or slender projections may be employed with the certainty that they will be effective. Where stone is scarce, brick buildings, with many arches, roughly constructed cornices and pilasters, and other peculiarities both of structure and ornamentation, make their appearance, as, for example, in Lombardy and North Germany. ”

“ In a marble country one should be always more and more astonished at the exquisite colour and structure of marble; in a slate country one should feel as if every rock cleft itself only for the sake of being built with conveniently.
Plate X.—Marble Masonry in the Duomo of Verona.
[Pg 377]
152. Now, for sculpture, there are, briefly, two materials—Clay, and Stone; for glass is only a clay that gets clear and brittle as it cools, and metal a clay that gets opaque and tough as it cools. ”

“ The twisted shafts of the upper stage of the Ducal Palace, and the triple and chevroned shafts of the Ca’ d’Oro, are not improvements upon the refinement of the earlier mode.
I have already spoken of the exquisite beauty of the inlaid marbles in S. Mark’s; nothing can be better than their effect, and nothing seems more wonderful than that they should not have been used more frequently in later buildings. I was, perhaps, a little disappointed in not finding, as I had expected, the marble arranged generally in geometrical patterns ”

“ It may be likened to a block of marble raised out of the quarry—rough and rude in outline, massive in solidity and strength, but giving no indication of the grace into which it will grow under the hand of the sculptor. What art effects upon the marble block, Nature accomplishes upon the surface of the land. ”

“ A kind of stone remarkable for its hardness and firm grain, and for being susceptible of the finest polish. It is dug in great masses from pits or quarries; and is much used in ornamental buildings, and for statues, altars, tombs, chimney-pieces, &c. The word is derived from the French marbre, marble. Marble is supposed to be formed, deep within the bowels of the earth, from a loose and porous carbonate of lime, subjected to enormous heat and pressure. ”

“ XVIII. It is well known, that what is meant by a church's being built of marble is, in nearly all cases, only that a veneering of marble has been fastened on the rough brick wall, built with certain projections to receive it; and that what appear to be massy stones, are nothing more than external slabs.
Now, it is evident, that, in this case, the question of right is on the same ground as in that of gilding. If it be clearly understood that a marble facing does not pretend or imply a marble wall, there is no harm in it ”

“ Only in this there is to be a certain respect for material also: for if we build in marble, or in any limestone, the known ease of the workmanship will make its absence seem slovenly; it will be well to take advantage of the stone's softness, and to make the design delicate and dependent upon smoothness of chiselled surfaces: but if we build in granite or lava, it is a folly, in most cases, to cast away the labor necessary to smooth it; it is wiser to make the design granitic itself, and to leave the blocks rudely squared. ”

“ Walls of enormous grandeur are developed or expanded without the few windows in them happening to impair their massiveness or diminish their strength. There are no flying buttresses; they are self-sustaining. Marble panels, alternately yellow and black, cover them with a glittering marquetry, and curves of arches let into their masses seem to be the bones of a robust skeleton beneath the skin. ”