"Pietra Dura" was a mosaic laid upon either a thick wood or a marble foundation. Lapis lazuli, malachite, and jasper were used largely, as well as bloodstones, onyx, and Rosso Antico. In Florentine Pietra Dura work, the inlay of two hard and equally cut materials reached its climax.

Arnolfo del Cambio, who built the Cathedral of Sta. Maria Fiore in Florence, being its architect from 1294 till 1310, was the first in that city to use coloured slabs and panels of marble in a sort of flat mosaic on a vast scale on the outside of buildings. His example has been extensively followed throughout Italy. The art of Pietra Dura mosaic began under Cosimo I. who imported it, if one may use such an expression, from Lombardy. It was used chiefly, like Gobelins Tapestry, to make very costly presents, otherwise unprocurable, for grandees and crowned heads. For a long time the work was a Royal monopoly. There are several interesting examples in the Pitti Palace, in this case in the form of tables. Flowers, fruits, sh.e.l.ls, and even figures and landscapes have been represented in this manner.

Six masters of the art of Pietra Dura came from Milan in 1580, to instruct the Florentines: and a portrait of Cosimo I. was the first important result of their labours. It was executed by Maestro Francesco Ferucci. The Medicean Mausoleum in Florence exhibits magnificent specimens of this craft.

In the time of Ferdinand I. the art was carried by Florentines to India, where it was used in decorating some of the palaces.

Under Ferdinand II. Pietra Dura reached its climax, there being in Florence at this time a most noted Frenchman, Luigi Siries, who settled in Florence in 1722. He refined the art by ceasing to use the stone as a pigment in producing pictures, and employing it for the more legitimate purposes of decoration. Some of the large tables in the Pitti are his work. Flowers and sh.e.l.ls on a porphyry ground were especially characteristic of Siries. There was a famous inlayer of tables, long before this time, named Antonio Leopardi, who lived from 1450 to 1525.

The inlay of wood has been called marquetry and intarsia, and was used princ.i.p.ally on furniture and choir stalls. Labarte gives the origin of this art in Italy to the twelfth century. The Guild of Carpenters in Florence had a branch of Intarsiatura workers, which included all forms of inlay in wood. It is really more correct to speak of intarsia when we allude to early Italian work, the word being derived from "interserere," the Latin for "insert;"

while marquetry originates in France, much later, from "marqueter,"

to mark. Italian wood inlay began in Siena, where one Manuello is reported to have worked in the Cathedral in 1259. Intarsia was also made in Orvieto at this time. Vasari did not hold the art in high estimation, saying that it was practised by "those persons who possessed more patience than skill in design," and I confess to a furtive concurrence in Vasari's opinion. He criticizes it a little illogically, however, when he goes on to say that the "work soon becomes dark, and is always in danger of perishing from the worms and by fire," for in these respects it is no more perishable than any great painting on canvas or panel. Vasari always is a little extreme, as we know.

The earliest Italian workers took a solid block of wood, chiselled out a sunken design, and then filled in the depression with other woods. The only enemy to such work was dampness, which might loosen the glue, or cause the small thin bits to swell or warp. The glue was applied always when the surfaces were perfectly clean, and the whole was pressed, being screwed down on heated metal plates, that all might dry evenly.

In 1478 there were thirty-four workshops of intarsia makers in Florence. The personal history of several of the Italian workers in inlay is still available, and, as it makes a craft seem much more vital when the names of the craftsmen are known to us, it will be interesting to glance at a few names of prominent artists in this branch of work. Bernardo Agnolo and his family are among them; and Domenico and Giovanni Ta.s.so were wood-carvers who worked with Michelangelo. Among the "Novelli," there is a quaint tale called "The Fat Ebony Carver," which is interesting to read in this connection.

Benedetto da Maiano, one of the "most solemn" workers in intarsia in Florence, became disgusted with his art after one trying experience, and ever after turned his attention to other carving. Vasari's version of the affair is as follows. Benedetto had been making two beautiful chests, all inlaid most elaborately, and carried them to the Court of Hungary, to exhibit the workmanship. "When he had made obeisance to the king, and had been kindly received, he brought forward his cases and had them unpacked... but it was then he discovered that the humidity of the sea voyage had softened the glue to such an extent that when the waxed cloths in which the coffers had been wrapped were opened, almost all the pieces were found sticking to them, and so fell to the ground! Whether Benedetto stood amazed and confounded at such an event, in the presence of so many n.o.bles, let every one judge for himself."

A famous family of wood inlayers were the del Ta.s.so, who came from S. Gervasio. One of the brothers, Giambattista, was a wag, and is said to have wasted much time in amus.e.m.e.nt and standing about criticizing the methods of others. He was a friend of Cellini, and all his cronies p.r.o.nounce him to have been a good fellow. On one occasion he had a good dose of the spirit of criticism, himself, from a visiting abbot, who stopped to see the Medicean tomb, where Ta.s.so happened to be working. Ta.s.so was requested to show the stranger about, which he did. The abbot began by depreciating the beauty of the building, remarking that Michelangelo's figures in the Sacristy did not interest him, and on his way up the stairs, he chanced to look out of a window and caught sight of Brunelleschi's dome. When the dull ecclesiastic began to say that this dome did not merit the admiration which it raised, the exasperated Ta.s.so, who was loyal to his friends, could stand no more. Il Lasca recounts what happened: "Pulling the abbot backward with force, he made him tumble down the staircase, and he took good care to fall himself on top of him, and calling out that the frater had been taken mad, he bound his arms and legs with cords... and then taking him, hanging over his shoulders, he carried him to a room near, stretched him on the ground, and left him there in the dark, taking away the key." We will hope that if Ta.s.so himself was too p.r.o.ne to criticism, he may have learned a lesson from this didactic monastic, and was more tolerant in the future.

Of the work of Canozio, a worker of about the same time, Matteo Colaccio in 1486, writes, "In visiting these intarsiad figures I was so much taken with the exquisiteness of the work that I could not withold myself from praising the author to heaven!" He refers thus ecstatically to the Stalls at St. Antonio at Padua, which were inlaid by Canozio, a.s.sisted by other masters. For his work in the Church of St. Domenico in Reggio, the contract called for some curious observances: he was bound by this to buy material for fifty lire, to work one third of the whole undertaking for fifty lire, to earn another fifty lire for each succeeding third, and then to give "forty-eight planks to the Lady," whatever that may mean! Among the instruments mentioned are: "Two screw profiles: one outliner: four one-handed little planes: rods for making cornices: two large squares and one grafonetto: three chisels, one glued and one all of iron: a pair of big pincers: two little axes: and a bench to put the tarsia on." Pyrography has its birth in intarsia, where singeing was sometimes employed as a shading in realistic designs.

In the Study of the Palace at Urbino, there is mention of "arm chairs encircling a table all mosaicked with tarsia, and carved by Maestro Giacomo of Florence," a worker of considerable repute.

One of the first to adopt the use of ivory, pearl, and silver for inlay was Andrea Ma.s.sari of Siena. In this same way inlay of tortoise-sh.e.l.l and bra.s.s was made,--the two layers were sawed out together, and then counterchanged so as to give the pattern in each material upon the other. Cabinets are often treated in this way. Ivory and sandal-wood or ebony, too, have been sometimes thus combined. In Spain cabinets were often made of a sort of mosaic of ebony and silver; in 1574 a Prohibtion was issued against using silver in this way, since it was becoming scarce.

In De Luna's "Diologos Familiarea," a Spanish work of 1669, the following conversation is given: "How much has your worship paid for this cabinet? It is worth more than forty ducats. What wood is it made of? The red is of mahogany, from Habana, and the black is made of ebony, and the white of ivory. You will find the workmanship excellent." This proves that inlaid cabinets were usual in Spain.

Ebony being expensive, it was sometimes simulated with stain. An old fifteenth century recipe says: "Take boxwood and lay in oil with sulphur for a night, then let it stew for an hour, and it will become as black as coal." An old Italian book enjoins the polishing of this imitation ebony as follows: "Is the wood to be polished with burnt pumice stone? Rub the work carefully with canvas and this powder, and then wash the piece with Dutch lime water so that it may be more beautifully polished... then the rind of a pomegranate must be steeped, and the wood smeared over with it, and set to dry, but in the shade."

Inlay was often imitated; the elaborate marquetry cabinets in Sta.

Maria della Grazia in Milan which are proudly displayed are in reality, according to Mr. Russell Sturgis, cleverly painted to simulate the real inlaid wood. Mr. Hamilton Jackson says that these, being by Luini, are intended to be known as paintings, but to imitate intarsia.

Intarsia was made also among the monasteries. The Olivetans practised this art extensively, and, much as some monasteries had scriptoria for the production of books, so others had carpenter's shops and studios where, according to Michele Caffi, they showed "great talent for working in wood, succeeding to the heirship of the art of tarsia in coloured woods, which they got from Tuscany." One of the more important of the Olivetan Monasteries was St. Michele in Bosco, where the noted worker in tarsia, Fra Raffaello da Brescia, made some magnificent choir stalls. In 1521 these were finished, but they were largely destroyed by the mob in the suppression of the convents in the eighteenth century. In 1812 eighteen of the stalls were saved, bought by the Marquis Malvezzi, and placed in St. Petronio. He tried also to save the canopies, but these had been sold for firewood at about twopence each!

The stalls of St. Domenico at Bologna are by Fra Damiano of Bergamo; it is said of him that his woods were coloured so marvellously that the art of tarsia was by him raised to the rank of that of painting! He was a Dominican monk in Bologna most of his life.

When Charles V. visited the choir of St. Domenico, and saw these stalls, he would not believe that the work was accomplished by inlay, and actually cut a piece out with his sword by way of investigation.

Castiglione the Courtier expresses himself with much admiration of the work of Fra Damiano, "rather divine than human." Of the technical perfection of the workmanship he adds: "Though these works are executed with inlaid pieces, the eye cannot even by the greatest exertion detect the joints.... I think, indeed, I am certain, that it will be called the eighth wonder of the world." (Count Castiglione did not perhaps realize what a wonderful world he lived in!) But at any rate there is no objection to subscribing to his eulogy: "All that I could say would be little enough of his rare and singular virtue, and on the goodness of his religious and holy life."

Another frate who wrote about that time alluded to Fra Damiano as "putting together woods with so much art that they appear as pictures painted with the brush."

In Germany there was some interesting intarsia made by the Elfen Brothers, of St. Michael's in Hildesheim, who produced beautiful chancel furniture. Hans Stengel of Nuremberg, too, was renowned in this art.

After the Renaissance marquetry ran riot in France, but that is out of the province of our present study.

The art of mosaic making has changed very little during the centuries.

Nearly all the technical methods now used were known to the ancients.

In fact, this art is rather an elemental one, and any departure from old established rules is liable to lead the worker into a new craft; his art becomes that of the inlayer or the enameller when he attempts to use larger pieces in cloissons, or to fuse bits together by any process.

Mosaic is a natural outgrowth from other inlaying; when an elaborate design had to be set up, quite too complicated to be treated in tortuously-cut large pieces, the craftsman naturally decided to render the whole work with small pieces, which demanded less accurate shaping of each piece. Originally, undoubtedly, each bit of gla.s.s or stone was laid in the soft plaster of wall or floor; but now a more labour saving method has obtained; it is amusing to watch the modern rest-cure. Instead of an artist working in square bits of gla.s.s to carry out his design, throwing his interest and personality into the work, a labourer sits leisurely before a large cartoon, on which he glues pieces of mosaic the prescribed colour and size, mechanically fitting them over the design until it is completely covered. Then this sheet of paper, with the mosaic glued to it, is slapped on to the plaster wall, having the stones next to the plaster, so that, until it is dry, all that can be seen is the sheet of paper apparently fixed on the wall. But lo! the grand transformation! The paper is washed off, leaving in place the finished product--a very accurate imitation of the picture on which the artist laboured, all in place in the wall, every stone evenly set as if it had been polished--entirely missing the charm of the irregular faceted effect of an old mosaic--again mechanical facility kills the spirit of an art.

Much early mosaic, known as Cosmati Work, is inlaid into marble, in geometric designs; twisted columns of this cla.s.s of work may be seen in profusion in Rome, and the facade of Orvieto is similarly decorated. Our ill.u.s.tration will demonstrate the technical process as well as a description.

The mosaic base of Edward the Confessor's shrine is inscribed to the effect that it was wrought by Peter of Rome. It was a dignified specimen of the best Cosmati. All the gold gla.s.s which once played its part in the scheme of decoration has been picked out, and in fact most of the pieces in the pattern are missing.

[Ill.u.s.tration: AMBO AT RAVELLO; SPECIMEN OF COSMATI MOSAIC]

The mosaic pavement in Westminster Abbey Presbytery is as fine an example of Roman Cosmati mosaic as one can see north of the Alps. An inscription, almost obliterated, is interpreted by Mr.

Lethaby as signifying, that in the year 1268 "Henry III. being King, and Odericus the cementarius, Richard de Ware, Abbot, brought the porphyry and divers jaspers and marbles of Thaso from Rome." In another place a sort of enigma, drawn from an arbitrary combination of animal forms and numbers, marks a chart for determining the end of the world! There is also a beautiful mosaic tomb at Westminster, inlaid with an interlacing pattern in a ground of marble, like the work so usual in Rome, and in Palermo, and other Southern centres of the art.

While the material used in mosaic wall decoration is sometimes a natural product, like marble, porphyry, coral, or alabaster, the picture is composed for the most part of artificially prepared smalts--opaque gla.s.s of various colours, made in sheets and then cut up into cubes. An infinite variety in gradations of colour and texture is thus made possible.

The gold grounds which one sees in nearly all mosaics are constructed in an interesting way. Each cube is composed of plain rather coa.r.s.e gla.s.s, of a greenish tinge, upon which is laid gold leaf. Over this leaf is another film of gla.s.s, extremely thin, so that the actual metal is isolated between two gla.s.ses, and is thus impervious to such qualities in the air as would tarnish it or cause it to deteriorate. To prevent an uninteresting evenness of surface on which the sun's rays would glint in a trying manner, it was usual to lay the gold cubes in a slightly irregular manner, so that each facet, as it were, should reflect at a different angle, and the texture, especially in the gold grounds, never became monotonous. One does not realize the importance of this custom until one sees a cheap modern mosaic laid absolutely flat, and then it is evident how necessary this broken surface is to good effect.

Any one who has tried to a.n.a.lyze the reason for the superiority of old French stained gla.s.s over any other, will be surprised, if he goes close to the wall, under one of the marvellous windows of Chartres, for instance, and looks up, to see that the whole fabric is warped and bent at a thousand angles,--it is not only the quality of the ancient gla.s.s, nor its colour, that gives this unattainable expression to these windows, but the accidental warping and wear of centuries have laid each bit of gla.s.s at a different angle, so that the refraction of the light is quite different from any possible reflection on the smooth surface of a modern window.

The dangers of a clear gold ground were, felt more fully by the workers at Ravenna and Rome, than in Venice. Architectural schemes were introduced to break up the surface: clouds and backgrounds, fields of flowers, and trees, and such devices, were used to prevent the monotony of the unbroken glint. But in Venice the decorators were brave; their faith in their material was unbounded, and they not only frankly laid gold in enormous ma.s.ses on flat wall and cupola, but they even moulded the edges and archivolts without separate ribs or strips to relieve them; the gold is carried all over the edges, which are rounded into curves to receive the mosaic, so that the effect is that of the entire upper part of the church having been _pressed_ into shape out of solid gold. The lights on these rounded edges are incomparably rich.

It is equally important to vary the plain values of the colour, and this was accomplished by means of dilution and contrast in tints instead of by unevenness of surface, although in many of the most satisfactory mosaics, both means have been employed. Plain tints in mosaic can be relieved in a most delightful way by the introduction of little separate cubes of unrelated colour, and the artist who best understands this use of ma.s.s and dot is the best maker of mosaic. The actual craft of construction is similar everywhere, but the use of what we may regard as the pigment has possibilities similar to the colours of a painter. The manipulation being of necessity slow, it is more difficult to convey the idea of spontaneity in design than it is in a fresco painting.

To follow briefly the history of mosaic as used in the Dark Ages, the Middle Ages, and the period of the Renaissance, it is interesting to note that by the fourth century mosaic was the princ.i.p.al decoration in ecclesiastical buildings. Contantine employed this art very extensively. Of his period, however, few examples remain. The most notable is the little church of Sta. Constanza, the vaults of which are ornamented in this way, with a fine running pattern of vines, interspersed with figures on a small scale. The Libel Pontificalis tells how Constantine built the Basilica of St. Agnese at the request of his daughter, and also a baptistery in the same place, where Constance was baptized, by Bishop Sylvester.

Among the most interesting early mosaics is the apse of the Church of St. Pudentiana in Rome. Barbet de Jouy, who has written extensively on this mosaic, considers it to be an eighth century achievement.

But a later archaeologist, M. Rossi, believes it to have been made in the fourth century, in which theory he is upheld by M. Vitet. The design is that of a company of saints gathered about the Throne on which G.o.d the Father sits to pa.s.s judgment. In certain restorations and alterations made in 1588 two of these figures were cut away, and the lower halves of those remaining were also removed, so that the figures are now only half length. The faces and figures are drawn in a very striking manner, being realistic and full of graceful action, very different from the mosaics of a later period, which were dominated by Byzantine tradition.

In France were many specimens of the mosaics of the fifth century.

But literary descriptions are all that have survived of these works, which might once have been seen at Nantes, Tours, and Clermont.

[Ill.u.s.tration: MOSAIC FROM RAVENNA; THEODORA AND HER SUITE, 16TH CENTURY]

Ravenna is the shrine of the craft in the fifth and sixth centuries.

It is useless in so small a s.p.a.ce to attempt to describe or do justice to these incomparable walls, where gleam the marvellous procession of white robed virgins, and where glitters the royal cortege of Justinian and Theodora. The acme of the art was reached when these mural decorations were planned and executed, and the churches of Ravenna may be considered the central museum of the world for a study of mosaic.

Among those who worked at Ravenna a few names have descended. These craftsmen were, Cuserius, Paulus, Ja.n.u.s, Statius and Stepha.n.u.s, but their histories are vague. Theodoric also brought some mosaic artists from Rome to work in Ravenna, which fact accounts for a Latin influence discernible in these mosaics, which are in many instances free from Byzantine stiffness. The details of the textiles in the great mosaics of Justinian and Theodora are rarely beautiful.

The chlamys with which Justinian is garbed is covered with circular interlaces with birds in them; on the border of the Empress's robe are embroideries of the three Magi presenting their gifts; on one of the robes of the attendants there is a pattern of ducks swimming, while another is ornamented with leaves of a five-pointed form.

There is a mosaic in the Tomb of Galla Placida in Ravenna, representing St. Lawrence, cheerfully approaching his gridiron, with the Cross and an open book enc.u.mbering his hands, while in a convenient corner stands a little piece of furniture resembling a meat-safe, containing the Four Gospels. The saint is walking briskly, and is fully draped; the gridiron is of the proportions of a cot bedstead, and has a raging fire beneath it,--a gruesome suggestion of the martyrdom.

No finer examples of the art of the colourist in mosaic can be seen than in the procession of Virgins at San Apollinaire Nuovo in Ravenna. Cool, restrained, and satisfying, the composition has all the elements of chromatic perfection. In the golden background occasional dots of light and dark brown serve to deepen the tone into a slightly bronze colour. The effect is especially scintillating and rich, more like hammered gold than a flat sheet. The colours in the trees are dark and light green, while the Virgins, in brown robes, with white draperies over them, are relieved with little touches of gold. The whole tone being thus green and russet, with purplish lines about the halos, is an unusual colour-scheme, and can hardly carry such conviction in a description as when it is seen.

In the East, the Church of Sta. Sophia at Constantinople exhibited the most magnificent specimens of this work; the building was constructed under Constantine, by the architects Anthemius and Isidore, and the entire interior, walls and dome included, was covered by mosaic pictures.

Among important works of the seventh century is the apse of St.

Agnese, in Rome. Honorius decorated the church, about 630, and it is one of the most effective mosaics in Rome. At St. John Lateran, also, Pope John IV. caused a splendid work to be carried out, which has been reported as being as "brilliant as the sacred waters."

In the eighth century a magnificent achievement was accomplished in the monastery of Centula, in Picardie, but all traces of this have been lost, for the convent was burnt in 1131. The eighth was not an active century for the arts, for in 726 Leo's edict was sent forth, prohibiting all forms of image worship, and at a Council at Constantinople in 754 it was decided that all iconographic representation and all use of symbols (except in the Sacrament) were blasphemous. Idolatrous monuments were destroyed, and the iconoclasts continued their devastations until the death of Theophilus in 842.

Fortunately this wave of zeal was checked before the destruction of the mosaics in Ravenna and Rome, but very few specimens survived in France.

In the ninth century a great many important monuments were added, and a majority of the mosaics which may still be seen, date from that time: they are not first in quality, however, although they are more numerous. After this, there was a period of inanition, in this art as in all others, while the pseudo-prophets awaited the ending of the world. After the year 1000 had pa.s.sed, and the astonished people found that they were still alive, and that the world appeared as stable as formerly, interest began to revive, and the new birth of art produced some significant examples in the field of mosaic. There was some activity in Germany, for a time, the versatile Bishop Bernward of Hildesheim adding this craft to his numerous accomplishments, although it is probable that his works resembled the graffiti and inlaid work rather than the mosaics composed of cubes of smalt.