the new-york exhibition illustrated.

MOSAICS.

HERE are few objects of art more entirely novelto American visitors at the Crystal Palace, thanthe Roman and Florentine mosaics—in theItalian epartment. This is one of the few• branches of art in which modern skill and tastehave shown themselves equal, and, indeed, su-perior to the ancient. The Florentine mosaicsin hard stones are almost exclusively of modernorigin. We allude of course to the employment of various naturalminerals cut and inlaid in a solid basis of black or other mar-ble, in such a manner as to produce the effect of a fine paint-ing. The ancients were well skilled in a method of then-own for producing mosaic pictures on walls and pavements,but their mode of the mosaic art was, as we shall presently show,quite distinct from the modern pietre dure , or hard stone mosaics.As this art in all its brandies is quite unknown in the UnitedStates, we propose to give some account of it for the informa-tion of the general reader,osaics are imitations of paintings and of natural objects, by means of coloredee, pieces of glass, and even of wood of different colors, cemented togetherh much art. The Italian musaieo and the French mosaique originated frome word musaicon of the Byzantine Greeks, who reintroduced the art intoa y in the 13th century, after it had been driven out in the fifth century by the^istracted state of the country during the fall of the Roman Empire. Little isthe^ 11 ear ^ history. It probably originated in the East, was improved bythe p re f^ CS ’ an< ^ was conveyed to Italy during the time of Sylla, a century beforetlii ilns ^ ai1 I^ ra - Some writers have amused themselves by tracing the origin ofthe 8 a ^. t0 ■^■ oses ) an< I from him its name. A more probable conjecture regardingth 0r - gIn narae that which refers it to the Greek word ixovtreiov, (museum)

. 6 01 ] omal meaning of which was a grotto consecrated to the Muses. From thocircumstance that mosaic work was often used for the decoration of the interiorgrottoes, the name of these rural retreats came to be applied naturally enoughto the work itself!

In Italy, and indeed in all countries occupied by the ancient Romans, many** ^ e nients and floors ornamented with mosaic work have been discovered. MoroP r °I'ably, than these, are the mosaic pavements discovered in the ruinsartliage. The ancient Roman mosaic was formed almost exclusively out ofSt AalI square bits of various colored marbles, serpentines, porphyries, and otherored stones set in a lime cement. These stones were arranged in various regu-patterns to form fretted borders—white and black being frequently the sole. 0rs while the central space was decorated either with geometrical figures, or^fh copies of various natural objects. The Romans were, however, by noans confined to the use of fragments of natural stones to produce their mosaics,u they also employed brilliantly colored enamels similar to those in use in theMosaics of modern Rome. Among the most celebrated of the ancient Roman^saics which have come down to our times is “Puny’s Doves” in the CapitolUs eum at Rome. This exquisite work is very perfectly preserved and represents° ar doves standing on the iip of a vase of water; one is drinking, while thohers are pluming their feathers. A beautiful border surrounds the composition,^hich was designed and used as a pavement in one of the apartments of a Roman°'ise. It -was found in Hadrian’s villa at Tivoli, in 1731, by Cardinal Fm-ietti.atural stones alone are used in its composition, and these are so small that 760av e been counted in a single square inch of the surface. This is believed bya htiq Uar ; es t£> p 6 £]j e game work of art which so excited the admiration of Pliny_ !a I_he describes it in his 35th book. He says, “ There is at Pergainos a wonderfulspecimen in mosaic of a dove drinking and darkening the water with the shadowler head, while on the lip of the vase others are pluming themselves.” Thisa utiful antique is so constantly reproduced in modern copies, both in mosaic and11 s culpture, that it is probably familiar to all.

. ^e excavations at Pompeii have brought to light numerous examples of an-® le nt Roman mosaics, and some of them are exquisitely beautiful, both in exeou-n an d design. Such is the noble composition known as the “Battue piece,”ov ^ le k° use °f toe Fawn, and now in the Museum at Naples, It contains^ 6r twenty figures of mounted horsemen in close conflict—some are fallen andco un( Ierfoot, while others are fiercely engaged hand to hand in deadly

>»bat. The gay costumes of the warriors—the polished circular shields incha 101 are seen reflections of the combatants—and especially the ancient war^ith V f ° Ur k° rses abreast > and containing apparently the leader of the onsetVe . °harioteer—all combine to produce a most spirited picture, and to Con-tois 8 ViVi<1 im P ressi °n °f toe arms and mode of ancient warfare. The figures in„j rem arkable mosaic are nearly of life size, and the colors are produced bys « enamels as well as by natural stones.

m l- 6 c ^ la ‘ ne< I dog with the inscription “ Gave Canem” (beware the dog), is afe-like and startling mosaic which formed the floor at the entrance of the

house of the Edile, Glaucus. Another well-known and beautiful example fromthe same city, is a casket of jewels, from the open top of which two doves aredrawing a necklace of pearls. This last-named mosaic has been suffered to re-main where it was found in the pavement of one of the apartments in the so-called house of Sallust. It is formed entirely of small squares of various naturalstones.

The only reprfsontative of the ancient Roman mosaic pavement found inmodern Italy is the Scagliola, in which irregular shaped fragments of various sizesof colored marble are imbedded in a calcareous cement, sometimes in symmetricalpatterns, and afterwards polished down to an even surface. Such are the com-mon floors of modern Italian houses—so well suited to the climate and habits ofthe country.

It has been suggested that the mosaic pavements of the Romans were formedby arranging the separate pieces in an inverted position on a flat surface uponwhich the design had been traced in outline, and then covering the back orunderside of the whole system of pieces with the cement which was to securethem in place. Afterward the whole mass being turned over and secured in itsdestined position, a perfectly level surface could be secured without the troubleof grinding or polishing down the irregularities which would certainly exist if themosaic had been formed in the position in which it was to remain, owing to thoimpossibility of inserting such minute fragments in a soft and yielding basis to aperfectly uniform level. This explanation is probably the true one.

The Modekn Roman Mosaics are exclusively of glass enamels. The prepara-tion of the pastes or colored glasses (always opaque), forms a separate branch ofindustry; they are made of very fusible materials, colored by oxyds of metals andtempered to every possible shade of color. It is said that the magazines of thepapal manufactory of mosaics in the Vatican, embrace not less than 10,000shades of the various colors. These enamels are drawn into rods or sticks likesealing-wax, of various sizes, according to the work to bo done, and are skilfullyarranged in a series of compartments to facilitate tho artist in the rapid prosecu-tion of his work. From the ends of these colored rods, bits are broken off bythe artist, who then sticks them upon a bed of soft cement, formed of quicklime,pulverized limestone and linseed oil. This cement is evenly spread upon a sur-face of metal or a slab of stone, and upon it is traced an outline of the picture orwork to he copied. Following this tracing, and with tho original pictures placedon an easel beside him, the artist proceeds in the most laborious and patientmanner to select and arrange the shades of color necessary to form a perfectcopy of the work. These tints must not only be skilfully selected for color, butthe individual bits must also he made to fit each other, leaving no spaces betweenthemselves. For this purpose he has frequent recourse to tho blow-pipe lamp, inwhose flame the enamel easily melts, and may be drawn out to the requiredsize and form. When the whole surface has been thus covered, some weeks ormonths are required for the cement to becomo hard and firm enough to withstandthe last process. This consists in grinding down by emery powder tho unevensurface of the mosaic, until a perfect level and a beautiful polish are produced. Itis only after this last step that the beauty of the design and the perfection of thework can be judged of. Before polishing, the surface presents only a dull, roughappearance—seemingly a very imperfect copy of the original. The time consumedin producing by this method copies of largo pictures is very great. For example,the transfiguration by Raphael, copied in mosaic for tho decoration of St. Peter’s(a mosaic probably 30 feet high), occupied several men over twenty years. Whenonce, however, a grand work is produced in mosaic, it is as nearly immortal as itis possible for man to make any thing. The materials employed are liablo to nochange from the causes which render oil paintings and even frescoes so destructi-ble. Undiminished in the brilliancy of its colors and untarnished by time, it goesdown to posterity exactly as it came from the hands of the artist. Fire may de-face and violence may destroy it, but from all other causes of decay and injury itis exempt. We well remember the feeling of amazement with which we gazedfor the first time on the mosaics of St. Peter’s and of St. Mark’s at Venice. It isonly by close inspection that the observer detects that tho beautiful copies withwhich St. Peter’s is lined are not either oil paintings or frescoes, so perfectly arethe forms and tints of the originals reproduced in so unmanageable a material asglass enamel.

For works to bo seen close at hand as in tables, brooches, and smallcopies of works of art, the size of tho individual pieces composing the mo-saic is very small, so that the several parts can be detected only by a closeinspection. On the other hand, for works to he placed in the domes of churchesor on lofty side-walls, the pieces employed are of considerable size. The dome ofSt. Peter’s for example, is entirely lined with gold mosaic, in which arc set mosaicmedallions of cherubs, angels, and other appropriate figures. From below, at the dis-tance of 400 feet, these have all the softness of paintings, but the observer isastonished on coming close to them to find the pieces of enamel so large that notmore than four are required for a square inch of surface. The size of the mosaicpieces selected for a given work must be the same for the whole surface, anymaterial change in this particular in the different parts of the same picture beingproductive of bad effects on the harmony and beauty of the whole. The gold