MOSAIC (late Greek psephosis, from psephos, a small stone; also mouseion, i.e., refined delicate work; hence the Latin opus musivum) is the fitting together of many, generally small, pieces of marble, opaque glass, coloured clays, or other substances, so as to form a pattern; the design may be of various degrees of elaboration, from the simplest, almost monochromatic, geometrical pattern to the most elaborate picture, with figure-subjects represented in colours of countless gradations.
The earliest existing specimens of mosaic belong to one of the less important branches of the art namely, the ornamentation on a small scale of jewellery, ivory thrones, and other furniture, or more rarely of some elaborate archi-tectural ornament. Most of this earliest sort of mosaic resembles in execution what are called cloisonnée enamels. In the Louvre and in the British Museum are preserved some very beautiful ivory carvings in low relief, some from Nineveh and others from Egypt, in which figures of deities, ornaments formed of the lotus and papyrus plants, and royal cartouches are enriched by small pieces of glass or lapis-lazuli and other gem-like stones, which are let into holes made in the ivory. Each minute piece is separated from the next by a thin wall or cloison of ivory, about as thick as cardboard, which thus forms a white outline, and sets off the brilliance of the coloured stones. The favourite pattern in this sort of work for decorating the larger surfaces appears to have been suggested by the feathers on a bird's wing. See IVORY, vol. xiii. pi. vii. fig. 3.
Recent excavations at Tel al-Yahudiya in Lower Egypt have brought to light some mosaics on a larger scale, but treated in the same way. These are caps of columns, wall tiles, and other objects, either of white limestone or earthen-ware, in which designs, chiefly some forms of the papyrus, are formed by brilliantly-coloured bits of glass or enamelled earthenware, let into a sinking in the tile or column. This form of mosaic was employed by the Greeks : the Erechtheum at Athens, built in the middle of the 5th century B.C., had the bases of some of its white marble columns ornamented with a plait-like design, in which pieces of coloured glass were inserted to emphasize the main lines of the pattern.
Another, quite different sort of mosaic was known to the Egyptians of the Ptolemaic and Roman periods. This is made entirely of glass, and is extremely minute. The finest known specimen is in the British Museum : it is a small tablet about three-eighths of an inch square, apparently the bezel of a ring, on which is represented the sacred hawk,every feather on the bird's wing being produced with a great number of colours and tints, each quite dis-tinct, and so minute that a strong magnifying glass is required to distinguish its details.
The way in which this wonderful little mosaic was pro-duced is extremely ingenious. Numbers of long sticks of various-coloured glass were arranged in such a way that their ends produced the figure of the hawk ; other sticks of blue glass were placed all round so as to form the ground. The whole bundle of sticks of glass when looked at endwise now presented the figure of the hawk with a blue background, immensely larger than it afterwards be-came. The bundle was then heated till the sticks melted together, and the whole thick rod, softened by fire, was then drawn out to a greatly-diminished thickness. In this process the relative positions of the sticks of coloured glass forming the design were not altered. A slice of the rod was then cut off, and its faces polished,the design, much reduced in size, of course being equally visible at both sides of the slice ; and thus the microscopic minute-ness of the mosaic was produced, with astonishing delicacy and refinement ; many slices, each showing the same mosaic, could be cut from the same rod.
The more important use of mosaic has been on a large scale either for pavements or for walls and vaulted ceil-ings. Mosaic for these purposes has by many writers, both ancient and modern, been divided on various systems into classes; perhaps the simplest classification is thefollowing:
I. For Pavements: (a) Tesselated, in which the design is formed of small cubes, generally of marble, more rarely of glass or clay; (b) Sectile, formed of larger pieces of marble, shaped and cut so as to fit accurately one with another. II. For Walls and Vaults:Fictile or vermiculated; pieces of opaque glass, in small cubes, arranged so as to form complicated pictures.
This classification is not altogether satisfactory, more than one method often being employed in the same mosaic; as, e.g., in the " opus Alexandrinum " of mediaeval writers, which is often partly tesselated and partly sectile.
Until Roman times we know but little of these kinds of mosaic. There is some evidence (in Pliny and other writers) to show that elaborate mosaic pavements, lithostroton [Greek] or lithologema [Greek], were made by the Greeks in the 4th century B.C., or even earlier; but most of the nu-merous fine specimens of tesselated work still existing in Greece, such as those at Sparta and Athens, must be referred to the time of the Roman occupation. The best examples of Hellenic mosaic are some pavements dis-covered during the recent excavations at Olympia (see fig. 1 and Ausgrabungen zu Olympia, 1877-82).
Among the Romans the use of mosaic, both of marble and opaque glass, was very extensive. According to Pliny (H.N., xxxvi. 25), they derived this art from the Greeks, but not until the time of the Third Punic War, 146 B.C., while glass mosaics for walls, "vitreae parietes," were a recent invention in his time. Many of these have been found at Pompeii; most commonly they are used to decorate niches for fountains or statuettes. Judging from the description given by Vitruvius (vii. 1), and an examina-tion of numerous specimens of Roman tesselated mosaics, the process of manufacture was the following. The earth was first
FIG. 1.Greek Pavement from the Temple of Zeus at Olympia.
carefully rammed down to a firm and even surface ; on this was laid a thick bed of stones, dry rubbish, and lime, called "rudus," from 6 to 9 inches deep, and above this another layer, 4 to 6 inches thick, called "nucleus," of one part of lime to three of pounded brick, mixed with wrater; on this, while still soft, the pattern could be sketched out with a wooden or metal point, and the tesserae or small bits of marble stuck into it, with their smoothest side uppermost. Lime, pounded white marble, and water were then mixed to the consistency of cream, forming a very hard-setting cement, called "marmoratum." This cement, while fluid, was poured over the marble surface, and well brushed into all the interstices between the tesserae. When the concrete and cement were both set, the surface of the pave-ment was rubbed down and polished. This kind of mosaic was largely used for floors of hypocausts ; the concrete bed was then supported on large tiles resting on numbers of short pillars.
If used for upper floors very strong joists were re-quired, and both Pliny (xxxvi. 25) and Vitruvius (vii. 1) recommend a double layer of boards, one crossing the other, on which the concrete and cement bedding was to be laid.
The usual Roman pavement was made of pieces of marble, averaging from a half to a quarter of an inch square, but rather irregular in shape. A few other, but quite exceptional, kinds of mosaic pavements have been found, such as that at the Isola Farnese, 9 miles from Rome, made of tile-like slabs of green glass, and a fine " sectile " pavement on the Palatine Hill, made of various-shaped pieces of glass, in black, white, and deep yellow. In some casese.g., in the " House of the Faun " at Pompeiiglass tesserae in small quantities have been mixed with the marble ones, for the sake of greater brilliance of colour. Pompeii is especially rich in its mosaics both on floor and walls, almost every house having at least its vestibule paved in this way.
In addition to graceful flowing patterns and geometrical de-signs, picture-like subjects of great elaboration frequently occur: of these the most important is the large and minutely-executed scene of the battle of Issus, found in the '' House of the Faun." It is of special value as being the chief classical historical picture still existing. It is a well-designed though somewhat crowded com-position, representing the moment of Alexander's victorious charge against the cavalry of Darius. The expression of the faces and the characteristic dresses of the Greeks and Persians are represented with great skill (see fig. 2). The tessene, as was always the case in this sort of work, are not all the same size, the smallest (only about one-tenth of an inch square) being reserved for the faces, where greatest refinement of detail was required. This was a floor-mosaic, though generally these minutely-executed works were affixed to walls.
The most skilfully-executed of all existing mosaics of this pictorial kind is that known as "Pliny's Doves," found in Hadrian's villa at Tivoli, and now in the Capitoline Museum. It may possibly be the one so highly praised by Pliny (xxxvi. 25) as the work of Sosus, for, although he describes it as being at Pergamum, yet it was a common practice with the Romans to transport these mosaics from one place to another, and this very celebrated one may well have been brought to Tivoli to adorn the emperor's villa. It is treated in a very realistic way : the light on the gold bowl, the plumage of the doves, and especially the reflexion in the water of the drinking dove, are represented with wonderful skill. It is, in fact, far too pictorial, and, like the late mosaics in St Peter's, Rome, is more remarkable for its technical skill than for any real artistic merit. This excessive realism, produced with great difficulty and cost, is a not uncommon fault of the more elaborate Roman mosaics, and was the inevitable result of the. luxury and ostentation of imperial Rome, which made art the bond-slave of the wealthy, rather than the free and natural expression of a whole people, as it was among the earlier Greeks.
Another interesting mosaic from the wall of a house at Pompeii, of extremely delicate work, is a rehearsal scene in a Greek theatre, where the chorcgus is instructing the actors: it is specially re-markable from its being signed as the work of Dioscorides of Samos. Other figure-subjects are not uncommon, such as various representations of the victory of Theseus over the Minotaur, others of Achilles in Scyros, many hunting scenes, and the like.
Throughout England, Germany, France, Spain, Asia Minor, and Northern Africa in no way have signs of Roman occupation been left so clearly and in so con-spicuous a form as by the numerous large and generally well-preserved mosaic pavements which have at various times been discovered in all these countries. In many cases, long after all traces of the walls of the buildings have disappeared, owing to their being dug up and re-moved for building purposes, the mosaics still remain to testify of the artistic power and mechanical skill of the Roman colonists.
Few countries are richer than England in these remains ; the great pavements of York, Woodchester, Cirencester, and many other places are as elaborate in design and as skilfully executed as any that now exist even in Rome itself. In whatever country these mosaics are found, their style and method of treatment are always much the same; the materials only of which the tesserae are made vary according to the stone or marble supplied by each country. In England, for instance, limestone or chalk often takes the place of the white marble so common in Italian and North African mosaics; while, instead of red marble, a fine sort of burnt clay or red sandstone is gene-rally used; other makeshifts had to be resorted to, and many of the Anglo-Roman mosaics are made entirely with-out marble. It is perhaps partly owing to the great wealth of Northern Africa in marbles of many colours and of varying shades that the finest of all Roman mosaics have been found in Algeria and Tunis, especially those from Carthage, some of which have been brought to the British Museum. See Archaeologia, vol. xxxviii. p. 202.
FIG. 2.Part of a Persian's Head from the Battle of Issus ; full size.
The range of colour in the marble tessera is very great, and is made use of with wonderful taste and skill: there are three or four different shades of red, and an equal number of yellows and greens, the last colour in all its tints being almost peculiar to this part of Africa, and one of the most pleasant and harmonious in almost any com-bination. Deep black, browns, and bluish-greys are also abundant. The white marble which forms the ground of nearly all the designs is often not pure white, but slightly striated with grey, giving great softness and beauty of texture to the surface, and doing away with too great monotony of tone. The Roman practice, common to .all their mosaics, of not fitting the tesserae quite closely together, but allowing the cement joints to show freely, was also of great value in giving effect to the general texture of the surfacea point quite forgotten by some later mosaic-workers, who thought that the closer their tesserae were fitted together the better the mosaic would be. This remark does not apply to sectile mosaic, in which sufficient variety can be given by the markings and veins in each piece of marble. To return to the mosaics from Carthage, they are no less excellent in design than in the richness and beauty of their materials. Large spaces are filled by grand sweeping curves of acanthus and other leaves, drawn with wonderful boldness and freedom of hand, and varied with great wealth of invention. With-out the use of very small tesserae, much richness of effect is given by gradations of tints, suggesting light and shade, without a painful attempt to represent actual relief. The colours of the marbles used here and elsewhere by the Romans are so quiet and harmonious that it would have been almost impossible to produce with them a harsh or glaring design, and when used with the skill and strong artistic feeling of the mosaic-workers at Carthage the result is a real masterpiece of decorative design. In Rome, and in the Roman colonies of Europe, this kind of marble tesselated mosaic was largely produced, with but little alteration in style or method of treatment, till the 4th century. In Syria and Asia Minor the art survived some centuries later.
Perhaps the latest existing example in Rome is that which deco-rates the vault of the ambulatory of the circular church of S. Costanza, built by Constantine the Great (320), outside the walls of Rome. This very interesting mosaic might from its style and materials have been executed in the 1st century, and is equal in beauty to any work of the kind in Italy. It shows no trace what-ever of the Byzantine influence which, in the next century, intro-duced into Italy a novel style of mosaic, in materials of the most glittering splendour. These S. Costanza mosaics are almost unique in Italy as an application of the old classical marble mosaic to the decoration of a Christian church. On the main compartment of the vault the surface is covered by vine branches, laden with grapes, twining in graceful curves over the space. In the centre is a large medallion with life-sized male bust, and at the lower part are vintage scenesoxen carts bringing the grapes, and boys treading them in a vat. Other more geometrical designs, of circles framing busts and full-length figures, with graceful borders, cover other parts of the vault. Farther east this classical style of mosaic appears to have lasted till the 6th century. At Kabr-Hiram, near Tyre, M. Ronan discovered among the ruins of a small three-apsed Christian church a fine mosaic pavement, covering the nave and aisles, thoroughly classical in style. The design, consisting of circles enclosing figures emblematic of the seasons, the months, and the winds, is almost the same as that of some mosaics discovered on the site of the Roman Italica near Seville, and others at Ephesus and Halicarnassus in Asia Minor. No trace of other than classical influence is visible, and yet it is pretty clear, from the evidence of an inscription, inlaid among the marble tessera, that the date of this pavement is not earlier than the latter part of the 6th century. A very similar mosaic, of about the same date, was discovered at Neby Yiinas, near Sidon.
Mediaeval Mosaics.These may be divided into four principal classes :(1) those used to decorate walls and vaults, made of glass cubes ; (2) those for pavements, made of marble, partly in large shaped pieces, and partly in small tesserae; (3) glass in small pieces, either rectangular or triangular, used to enrich marble pulpits, columns, and other architectural features ; (4) wood mosaics.
1. The wall mosaics were, in their origin, purely Byzan-tine, and appear to date from the beginning of the 5th century. They are made of coloured glass, rendered opaque by the addition of oxide of tin. The melted glass was cast into flat slabs, generally about half an inch thick, and then broken into small cubes. Every possible colour and grada-tion of tint was produced by the mediaeval glassmakers. Tesserae of gold (which were very largely used) and of silver were made thus:the metal leaf was spread over one of the glass slabs, the colour of which did not matter, as it was hidden by the gold or silver; over this metal-coated slab a skin of colourless glass was fused, so as to protect the metal leaf from injury or tarnish; and then the slab was broken up into cubes, the xj/rjcpoc xpfxreoi of Byzantine writers.
The method of putting together the mosaic was much the same as that employed by the Romans in their tesse-lated pavements. A thick coat of cement was applied to the wall or vault, the outline indicated with a metal point, and the cubes stuck one by one into the cement while it was yet soft,the main difference being that no rubbing down and polishing were required, the faces of the glass tesserae showing the natural surface of the fracture, which was not quite level, and by this slight inequality of surface great additional lustre and brilliance of effect were given to the whole picture.
Owing to the intense conservatism of Byzantine art, no regular stages of progression can be traced in this class of mosaic. Some of the 5th century mosaics at Ravenna are, in every way, as fine as those of the 12th, and it was not till the end of the 13th century that any important change in style took place, when Cimabue, and more especially his pupils Jacopo da Turrita and Taddeo Gaddi, applied their increased knowledge of the human form and of the harmonies of colour to the production of the most beau-tiful of all mosaics, such as those in the apse of S. Maria Maggiore in Rome. It must not, however, be supposed that during all this time (from the 5th to the 14th century) one steady level of excellence was kept up. The mosaics of the 9th century are inferior in drawing and general treatment to those both of the earlier and later time, while in Italy at least this art was almost entirely extinct during the 10th and 11th centuries. Extreme splendour of colour and jewel-like brilliance combined with the most stately grandeur of form are the main characteristic of this sort of decoration. Its most frequent application is to the sanc-tuary arch and apse of the early basilicas.
A "majesty," or colossal central figure of Christ with saints standing on each side, is the most frequent motive. In many cases, especially in the 5th and 6th centuries, Christ was represented as a lamb, to whom the twelve apostles, in the form of sheep, are paying adoration. Christ, the Good Shepherd, is sometimes depicted as a beardless youth, seated among a circle of sheepthe treatment of the motive being obviously taken from pagan representations of Orpheus playing to the beasts. The tomb of Galla Placidia has a good example of this subject, with much of the old Roman grace in the drawing and composition. Frequently the Virgin Mary, or the patron saint of the church, occupies the central space in the apse, with ranges of other saints on each side.
The " Doom," or Last Judgment, is a favourite subject for domes and sanctuary arches; the Florence baptistery has one of the grandest mosaic pictures of this subject, executed in the 13th century. The earlier baptisteries usually have the scene of Christ's baptism,the river Jordan being sometimes personified in a very classical manner, as an old man with flowing beard, holding an urn from which a stream pours forth. S. Vitale at Ravenna lias in the sanctuary a very interesting representation of Justinian and his empress Theo-dora (see fig. 3), attended by a numerous suite of courtiers and ladies ; these mosaics are certainly of the 6th century, and may be contemporary with Justinian, though the fact that he and Theodora are each represented with a circular nimbus appears to indicate that they were not then alive. Scenes from both Old and New Testaments or the lives of the saints are also represented in almost endless variety,generally on the walls of the body of the church, in square-shaped pictures, arranged in one or more tiers over the nave columns or arcade.
In mosaics of the best periods the treatment of the forms and draperies is broad and simple, a just amount of relief being expressed by delicate gradations of tints. In mosaics of the 9th century the drawing is very awkward, and the folds of the robes are rudely expressed in outline, with no suggestion of light and shade.
A further application of this work was to the decoration of broad bands over the columns of the nave, as at S. Maria Maggiore in Rome, 5th century, and in the two churches of S. Apollinare at Ravenna, 6th century. In some cases almost the whole interior of the church was encrusted in this magnificent way, as at Monreale Cathedral, the Capella Palatina of Palermo, and S. Mark's at Venice, the magnificence of which no words can describe; it is quite unrivalled by that of any other buildings in the world. See MONREALE.
In these churches the mosaics cover soffits and angles entirely, and give the effect of a mass of solid gold and colour producing the utmost conceivable splendour of decoration [853-1]. In many cases vaulted ceilings were covered with these mosaics, as the tomb of Galla Placidia, 450 A.D., and the two baptisteries at Ravenna, 5th and 6th centuries. For exteriors, the large use of mosaic was usually confined to the west facade, as at S. Miniato, Florence, S. Maria Maggiore, Rome, and S. Mark's, Venice. In almost all cases the figures are represented on a gold ground, and gold is freely used in the dresses and ornamentsrich jewels and embroidery being represented in gold, silver, sparkling reds, blues, and other colours, so as to give the utmost splendour of effect to the figures and their drapery.
FIG. 3.Mosaic of Theodora and attendants, from S. Vitale, Ravenna ; over life-size.
The revival of the art of painting in Italy and the introduction of fresco work in the 14th century gave the deathblow to the true art of wall-mosaics. Though at first the simple and archaic style of Cimabue and his pupils Jacopo da Turrita, Giotto, and Taddeo Gaddi was equally applicable to painting or mosaic, yet soon the development of art into greater realism and complexity required a method of expression unfettered by the necessi-ties and canons of mosaic-work. Pietro Cavallini, a Roman artist, was one of the last who worked according to the old traditions. His mosaic of the birth of the Virgin in S. Maria in Cosmedin, Rome, executed about the middle of the 14th century, is not without merit, though his superior knowledge of form has only caused his composi-tion to be somewhat feeble and insipid compared with the works of the earlier artists. Even in the 15th century a few good mosaics were produced at Venice and elsewhere. Since then many large pictures have been copied in glass mosaic, generally attempts to imitate oil paintings, executed with great skill and wonderful patience, but all utterly worthless as works of art, merely costly monuments of human folly and misapplied labour. The mosaics from Titian's pictures on the west end of S. Mark's at Venice, Raphael's in the Chigi Chapel in S. Maria del Popolo, and many large pictures in S. Peter's in Rome, are the most striking examples of these.
The following list, in chronological order, comprises a selection from among the most important mediaeval glass wall-mosaics during the period when mosaic-working was a real art:
Tomb of Galla Placidiavault, 450.
S. Paolo fuori le muratriumphal aroh.
S. Maria Maggioresquare pictures over nave columns, and triumphal arch.
S. Ambrogio, Chapel of S. Satirovault.
S. Apollinare Nuovoapse and nave, with 9th century additions.
S. Vitaleapse and whole sanctuary, cirai 547.
S. Apollinare in Classeapse and nave, 549.
SS. Cosmas and Damianapse.
S. Lorenzo, Chapel of S. Aquilinusvault.
S. Sophiawalls and vault, circa, 550.
Church of St George-apse, &c.; and S. Sophia-dome and apse.
Trebizond. S. Sophiaapse.
S. Agnese fuori le muraapse, 626.
"Dome of the Rock "arches of ambulatory, 688.
Baptistery of S. Giovanni in Laterano.
SS. Nereus and Achilles.
Mosque of Al-Aksa on dome.
Chapel of the Transfiguration.
S. Cecilia in Trastevereapse
S. Maria delia Navioellaapse, and "Chapel of the Column.
S. Prassedetriumphal arch.
S. Pudenziana, 884.
S. Ambrogioapse, 832.
Mihrab (sanctuary) of Mosque.
" Dome of the Rock "base of cupola, 1027.
Church of S. Saviourwalls and domes.
S. Mark'snarthex, apse, and walls of nave and aisles.
Capella Palatina, begun 1132the whole walls.
Church of La Martoranavault.
Cathedralthe whole walls, 1170-90.
Church of the Nativity, 1169.
S. Franeesca Romanaapse.
S. Maria in Trastevereapse.
Baptistery vault, begun c. 1225 by Fra Jacopo.
S. Miniatoapse and west front.
S. Paolo fuori le muraapse.
S. Clementetriumphal arch, 1297.
S. Giovanni in Lateranoapse by Jacopo da Turrita, 1290.
S. Maria Maggioreapse and west end by Jacopo da Turrita. 1292-1299, and Taddei Gaddi.
Baptistery, finished by Andrea Tail.
Cathedraleast apse by Cimabue, 1302, north and south apses by his pupils.
S. Peter'snavicella, in atrium by Giotto.
8. Maria in Cosmedinon walls by Pietro Cavallini, e. 1340.
SS. Giovanni e Paoloin arch over effigy of Doge Morosmi.
This list is by no means exhaustive, and only gives some of the best and most typical examples of the mosaic-work of each century.
The Byzantine origin of these great wall-mosaics, wherever they are found, is amply proved both by internal and documentary evidence. The gorgeous mosaics of S. Sophia and S. Saviour's in Constantinople, 6th century, and the later ones in the monasteries of Mount Atlios, at Salonica and at Daphne near Athens, are identical in style with those of Italy of the same date. Moreover, the even more beautiful mosaic-work in the " Dome of the Rock " at Jerusa-lem, 7th and 11th centuries, and that in the sanctuary of the great mosque of Cordova, of the 10th century, are known to be the work of Byzantine artists, in spite of their thoroughly Oriental design. The same is the case with the rarer mosaics of Germany, such as those in S. Gereon at Cologne and at Parenzo.
A very remarkable, almost unique, specimen of Byzantine mosaic is now preserved in the "Opera del Duomo," Florence. This is a diptych of the 11th century, of extremely minute, almost micro-scopic, work, in tessera of glass and metal, perhaps the only example of tessera made of solid metal. It has figures of saints and inscrip-tions, each tessera being scarcely larger than a pin's head. This beautiful diptych originally belonged to the imperial chapel in Con-stantinople, and was brought to Florence in the 14th century.
2. The second mediarval class, mosaic pavements, though of great beauty, are of less artistic importance.
This so-called " opus Alexandrinum " is very common throughout Italy and in the East, and came to greatest perfection in the 13th century. It is made partly of small marble tessera forming the main lines of the pattern, and partly of large pieces used as a ground j or matrix. It is generally designed in large flowing bands which interlace and enclose circles, often of one stone sliced from a column. The finest example is that at S. Mark's, Venice, of the 12th century. The materials are mainly white marble, with green and red porphyry, and sometimes glass.
Besides the countless churches in Italy possessing these beautiful pavements, such as S. Lorenzo, S. Marco, S. Maria Maggiore, and S. Maria in Trastevere, in Rome, we have, in the Chapel of the Confessor, and in front of the high altar at Westminster, very fine specimens of this work, executed about 1268 by a Roman artist called Odericus, who was brought to England by Abbot Ware, on the occasion of a visit made by the latter to Rome. Another English example is the mosaic pavement in front of the shrine of Becket at Canterbury ; this is probably the work of an Englishman, though the materials are foreign, as it is partly inlaid with bronze, a peculiarity never found in Italy. There are also many fine examples of these pavements in the churches of the East, such as that in S. Sophia at Trebizond, of the most elaborate design and splendid materials, very like the S. Mark's pavement at Venice. Palermo and Monreale are especially rich in examples of sectile mosaic, used both for pavements and walls,in the latter case generally for the lower part of the walls, the upper part being covered with the glass mosaics. The designs of these Sicilian works, mostly executed under the Norman kings in the 12th century, are very Oriental in character, and in many cases were actually executed by Moslem workmen. Fig. 4 gives a specimen of this mosaic from Monreale cathedral. Its chief characteristic is the absence of curved lines, so largely used in the splendid opus Alexandrinum of Italy, arising from the fact that this class of Oriental design was mainly used for the delicate panelling in wood on their pulpits, doors, &c,wood being a material quite unsuited for the production of large curves.
FIG. 4.Marble Mosaic at Monreale Cathedral.
3. Glass mosaic, used to ornament ambones, pulpits, tombs, bishops' thrones, baldacchini columns, architraves, and other marble objects, is chiefly Italian. The designs, when it is used to enrich flat surfaces, such as panels or architraves, are very similar to those of the pavements last described. The white marble is used as a matrix, in which sinkings are made to hold the glass tessera; twisted columns are frequently ornamented with a spiral band of this glass mosaic, or flutings are suggested by parallel bands on straight columns. The cloisters of S. Giovanni in Laterano and S. Paolo fuori le mura have splendid examples of these enriched shafts and architraves.
This style of work was largely employed from the 6th to the 14th centuries. One family in Italy, the Cosmati, during the whole of the 13th century, was especially skilled in this craft, and the various members of it produced an extraordinary amount of rich and beauti-ful work. The pulpit in S. Maria in Ara Cceli, Rome, is one of the finest specimens (see fig. mente and S. Lorenzo, and that in Salerno cathedral. The tomb of Henry III., 1291, and the shrine of the Confessor, 1269, at Westminster are the only examples of this work in England. They were executed by " Petrus civis Romanus," probably a pupil of the Cosmati.
In India, especially during the 17th century, many Mohammedan buildings were decorated with fine marble inlay of the classnow called'' Florentine." This is sectile mosaic, formed by shaped pieces of various-coloured marbles let into a marble matrix. A great deal of the Indian mosaic of this sort was executed by Ital-ian workmen ; the finest examples are at Agra, such as the Taj Mehal [Taj Mahal].
The modern so-called "Roman mosaic" is formed of short and slen-der sticks of coloured glass fixed in cement, the ends, which form the pattern, being finally rubbed down and polished.
Many not unsuccessful attempts have been made lately to reproduce the Roman tesselated work for pavements; and at Murano, near Venice, glass wall-mosaics are still pro-duced in imitation of the magnificent works of medieval times.
4. Mosaics in wood are largely used in Mohammedan buildings, especially from the 14th to the 17th centuries. The finest specimens of this work are at Cairo and Damascus, and are used chiefly to decorate the magnificent pulpits and other woodwork in the mosques. The patterns are very delicate and complicated, worked in inlay of small pieces of various-coloured woods, often further en-riched by bits of mother-of-pearl and minutely carved ivory. The general effect is extremely splendid from the combined beauties of the materials and workmanship, as well as from the marvellous grace and fancy of the designs. This art was also practised largely by the Copts of Egypt, and much used by them to ornament the magnificent iconostases and other screens in their churches.
Another application of wood to mosaic-work, called "intarsia-tura," was very common in Italy, especially in Tuscany and Lom-bardy, during the 15th and early 16th centuries. Its chief use was for the decoration of the stalls and lecterns in the church-choirs. Very small bits of various-coloured woods were used to produce goemetrical patterns, while the figure-subjects , views of buildings with strong perspective effects, and even landscapes, were very skilfully produced by an inlay of larger pieces. Ambrogio Borgognone, Raphael, and other great painters often drew the designs for this sort of work. The mosaic figures in the panels of the stalls at the
FIG. 5.Part of Marble Pulpit with glass mosaic, church of Ara Cceli, Rome.
Certosa near Pavia were by Borgognone, and are extremely beauti-ful. The stalls in Siena cathedral and in S. Pietro de' Casinensi at Perugia, the latter from Raphael's designs, are among the finest works of this sort, which are very numerous in Italy. It has also been used on a smaller scale to ornament furniture, and especially the " Cassoni," or large trousseau coffers, on which the most costly and elaborate decorations were often lavished. Some traditional skill in this art still lingers in Italy, especially in the city of Siena.
Classical Mosaics.Pliny, H. N. [Historia Naturalis], xxxvi. ; Vitruvius ; Franks, Slade Collection of Ancient Glass, and Excavations at Carthage, 1860 ; Artaud, Histoire de la peinture en mosaïque, 1835 ; Monumentos Arquitectonicos de Espana (" Italica," "Cordoba," and "Elche"), 1859-83 ; Laborde, Mosaïque d'Italica, près de Seville, 1802 ; Ciampini, Vetera Monumenta, Rome, 1747 ; Von Munitoli, Mosaikfussboden, &c, 1835 ; Lysons, Mosaics of Horkstow, 1801, and Roman Antiquities of Woodchester, 1797 ; Mazois, Les ruines de Pompei, Paris, 1812-38 ; Real Museo Borbonico, various dates ; Roach Smith, Roman London, 1859 ; Ausgrabungen zu Olympia, 1877-82.
Christian.Theophilus, Diversarum Artium Schedula, ii. 15 ; S. Kensington Museum Art Inventory, part i., 1870; Renan, Mission de Phènicie, 1875 ; Garrucci, Arte Cristiana, 1S72-S2, voi. iv. ; De Rossi, Musaici Cristiani di Roma, 1872-82 ; Parker, Archaeology of Rome, and Mosaic Pictures in Rome and Ravenna, 1866 ; Jouy, Les Mosaïques chrétiennes de Rome, 1857 ; Gravina, Duomo di Monreale, Palermo, 1859 sq. ; Serradifalco, Monreale ed altre chiese Siculo-Normanne, 1838 ; Salazaro, Mon. dell' Arte Merid. d'Italia, 1882 ; M. D. Wyatt, Geometrical Mosaics, of the Middle Ages, 1849 ; Salzenberg, Alt-Christliche Baudenkmale von Constantinopel, 1854 ; Pulgher, Églises Byzantines de Constantinople, 1883 ; Texier and Pullan, Byzantine Architecture, 1864; Quast, Alt-Christlichen Bauwerke von Ravenna, Ì842 ; De Vogué, Églises de la 'ferre Sainte, I860 ; Milanesi, Bel Arte del Vetro pel Musaico, 16th century (reprinted at Bologna in 1864) ; Rohault de Fleury, Monuments de Pise, 1866 ; Kreutz, Basilica di S. Marco, Venezia, 1S43 ; Gally Knight, Ecclesiastical Architecture of Italy, 1842-4; Fossati, Aya Sophia, 1852; Didron, "La peinture en Mosaïque," Gaz. des B. Arts, vol. xi., p. 442; Gerspach, La Mosaïque, 18S3.
Moslem. Hessemer, Arabische und Alt-Italienische Bau-Verzierungen, 1853 ; Prisse d'Avennes, L'Art Arabe, 1874-1880 ; Prangey, Mosquée de Cordoue, 1830 ; Owen Jones, Alhambra, 1842 ; De Vogué, Temple de Jérusalem, 1864 ; Texier, Asie Mineure, 1862, and L'Arménie et la Perse, 1842-52 ; Bourgoin, Les Arts Arabes, 186S ; Coste, Monuments modernes de la Perse, 1867 ; Flandin and Coste, Voyage en Perse, 1843-54.
Wood-MosaicTarsia.Ornati del Coro di S. Pietro Cassinense di Perugia,
1830 ; Calli, various works on Rafaello da Brescia and other intarsiatori, 1851,
&c. ; Tarsie ed intagli di S. Lorenzo in Genova, 1878. (J. H. M.)
[853-1] Unfortunately the world-wide fame of S. Mark's and the other great churches of Italy has subjected these extraordinary works to the fatal, process of " restoration," and wherever any sign of decay in the cement backing (the tessera themselves are quite indestructible) has given the least excuse the "restorers " have destroyed whole masses of ancient work, and supplied its place with worthless modern copies. The mosaics of the S. Mark's baptistery, and of the apses at S. Miniato, at Pisa, and many other places have in this way been wantonly renewed within the last few years.
The above article was written by: J. H. Middleton.