mosaic (mōzā`ĭk), art of arranging colored pieces of marble, glass, tile, wood, or other material to produce a surface ornament.

Ancient Mosaics

In Egypt and Mesopotamia, furniture, small architectural features, and jewelry were occasionally adorned with inset bits of enamel, glass, and colored stone. Early Greek mosaics (5th–4th cent. B.C.) uncovered at Olynthus were worked in small natural pebbles. The use of cut cubes or tesserae was introduced from the East after the Alexandrian conquest. Roman floor mosaics were probably based upon Greek examples, and glass mosaics applied to columns, niches, and fountains can be seen at Pompeii. In Italy and the Roman colonies the floor patterns were produced both by large slabs of marble in contrasting colors (opus sectile) and by small marble tesserae (opus tessellatum). The tessera designs varied from simple geometrical patterns in black and white to huge pictorial arrangements of figures and animals; examples were found in Rome, Pompeii, Antioch and Zeugma (S Turkey), and N Africa.

Early Christian Mosaics

In the early centuries A.D. glass mosaics brought color and decoration to the broad walls of the basilicas. By the 4th cent. the triumphal arch between nave and apse and the walls above the nave arcades received mosaic adornment, while the entire domed apse was lined with a mosaic picture, generally of Jesus surrounded by saints and apostles.

In this period Byzantium (later Constantinople) became the center of the craft, which reached perfection in the 6th cent. Hagia Sophia Hagia Sophia (hä`jə sōfē`ə, hā`jēə,) [Gr.
..... Click the link for more information. exhibits glittering gold backgrounds—a special feature of Eastern mosaic art, which later spread to the West. A gold tessera was produced by applying gold leaf to a glass cube and covering it with a thin glass film to protect against tarnishing; for the other tesserae the colors were produced by metallic oxides. The tesserae were set by hand in the damp cement mortar, and the resulting irregularities, causing the facets to reflect at different angles, were an essential factor of effect. In the 5th and 6th cent. Ravenna Ravenna (rävĕn`nä), city (1991 pop. 135,844), capital of Ravenna prov.
..... Click the link for more information. became the Western center of mosaic art, and the Ravenna masterworks (e.g., the decoration of San Vitale), as well as those in Rome, show the Byzantine characteristics of stylized rigidity in the figures.

Medieval Mosaics

Through the importation of Greek workmen, a revival took place in Italy in the 11th cent. which lasted into the 13th cent., producing the beautiful mural works of Rome, of Saint Mark's Church Saint Mark's Church, Venice, named after the tutelary saint of Venice. The original Romanesque basilical church, built in the 9th cent. as a shrine for the saint's bones, was destroyed by fire in 967.
..... Click the link for more information. and Torcello at Venice, and of Palermo, Monreale, and Cefalù in Sicily. Rich medieval marble and mosaic floors with geometric patterns appeared in Italy, Sicily, and the East. In Russia, especially in Kiev, remarkable figural mosaics were set into the walls.

From the 13th cent., mosaic in Italy and Sicily extended to many architectural elements, such as pulpits, bishops' thrones, paschal candlesticks, and the twisted columns of cloisters. These adornments are commonly termed Cosmati work, after the family of Roman artisans especially gifted in their execution. The rise of fresco decoration in the early 14th cent. in Italy superseded mosaic, which then began to deteriorate into mere simulation of painting, although it lingered in Venice, Greece, and Constantinople.

Modern Mosaics

The Gothic revival of the 19th cent. produced some modern attempts, as in Westminster Abbey and the houses of Parliament. In the 20th cent. the medium has been used with truer understanding of techniques, as in the modernist mosaics for the Stockholm town hall. In modern work the ancient system shares favor with a new method of fastening the tesserae with glue upon a paper cartoon drawn in reverse, applying fairly large sections of this into proper position upon the damp mortar, and then washing away the paper after the mortar has hardened and the tesserae have set.

Bibliography

See E. W. Anthony, A History of Mosaics (1935, repr. 1968); F. Rossi, Mosaics: A Survey of Their History and Techniques (1970); J. R. Clark, Roman Black-and-White Figural Mosaics (1985).

mosaic

Surface decoration of small coloured components—such as stone, glass, tile, or shell—closely set into an adhesive ground. Mosaic pieces, or tesserae, are usually small squares, triangles, or other regular shapes. Mosaics cannot create the variations of light and shadow that paintings can, but glass tesserae can achieve a greater brilliance, especially those to which gold and silver foil have been applied. This technique was responsible for the great shimmering mosaics of the Byzantine period. The earliest known mosaics date from the 8th century BC and were made of pebbles, a technique refined by the Greeks in the 5th century. The Romans used mosaics widely, particularly for floors. Pre-Columbian Americans favoured mosaics of garnet, turquoise, and mother-of-pearl, which usually encrusted shields, masks, and cult statues.

The Web browser created by Marc Andreessen, Eric Bina and others at the University of Illinois National Center for Supercomputing Applications (NCSA). It was the first multimedia browser for the Web, allowing text, images, sound and video to be accessed via a graphical user interface.

The "Killer App" of the Web
Mosaic was released on the Internet in 1993 and became "the" application that caused the Web to explode. Originally developed for Unix, it was ported to Windows and Mac within a few months. Both Andreessen and Bina later went to work for Mosaic Corporation, which was formed to market Mosaic, but wound up developing the Netscape browser. The company was renamed Netscape, and the Netscape browser reigned supreme for a while.

The University eventually licensed Mosaic to Spyglass, Inc., which Microsoft acquired. Thus, the Mosaic browser ultimately evolved into Internet Explorer. See Web browser and Netscape.

Mosaic Browser
Looking very much like any of today's browsers, Mosaic was a major catalyst in revolutionizing the world. It helped cause the Web to explode, and ultimately, the Internet to go commercial. (Image courtesy of the National Center for Supercomputing Applications (NCSA) and the Board of Trustees of the University of Illinois.)

(World-Wide Web, tool)

Mosaic - NCSA's browser (client) for the World-Wide Web.

Mosaic has been described as "the killer application of the 1990s" because it was the first program to provide a slick multimedia graphical user interface to the Internet's burgeoning wealth of distributed information services (formerly mostly limited to FTP and Gopher) at a time when access to the Internet was expanding rapidly outside its previous domain of academia and large industrial research institutions.

NCSA Mosaic was originally designed and programmed for the X Window System by Marc Andreessen and Eric Bina at NCSA. Version 1.0 was released in April 1993, followed by two maintenance releases during summer 1993. Version 2.0 was released in December 1993, along with version 1.0 releases for both the Apple Macintosh and Microsoft Windows. An Acorn Archimedes port is underway (May 1994).

Marc Andreessen, who created the NCSA Mosaic research prototype as an undergraduate student at the University of Illinois left to start Mosaic Communications Corporation along with five other former students and staff of the university who were instrumental in NCSA Mosaic's design and development.

http://ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/help-about.html.

ftp://ftp.ncsa.uiuc.edu/.

E-mail: <mosaic-x@ncsa.uiuc.edu> (X version), <mosaic-mac@ncsa.uiuc.edu> (Macintosh), <mosaic-win@ncsa.uiuc.edu> (Windows version), <mosaic@ncsa.uiuc.edu> (general help).