GLASS. — The most ancient examples of glassmaking with an artistic character in the Mediterranean basin date back to the eighteenth dynasty of Egyptian Pharaohs (1550 B.C.) and are represented by small polychrome unguentaria, in which the decoration was obtained by pouring a thread of molten enamel onto the vessel in spiral patterns.
However, this art saw more significant development later in the centers of Phoenicia, particularly at Sidon, with glass blown into clay molds, and from there vases, cups, and bottles were imported into Etruria (attested by tombs between the 7th and 5th centuries B.C.), while in Pompeii and Augustan Rome blown glass of considerable size was produced under the influence of Syrian and Sidonian artists. In the subsequent imperial period, glass of Greco-Egyptian style was produced in Alexandria, where technical virtuosity displayed various striations, serpentine motifs, spirals, stars, rosettes, tesserae with masks and flowers, as well as engravings and grooves made with a wheel and gilding applied by thin metal leaf. No technical innovations occurred during the Paleochristian and Byzantine periods, which saw the transfer of glassmaking to the East, enriched with chromatic motifs, especially in pastes for goldsmithing and mosaic tesserae, and then in the Arab world. After the 11th century, Western Europe saw a revival of forms and execution techniques, with notable production in Altare, in the province of Savona, and in Venice. From here, in the latter part of the 13th century, such industries concentrated on the island of Murano, where the 14th-century master Giovanni Fioler gained fame, and in the following century, the workshop of Angelo Barovier and his son Marino, who produced characteristic blue and lattimo glassworks and enameled pieces of splendid colors, such as the nuptial cups in the Murano and Bologna museums, the glass in the National Museum of Florence, where the Triumph of Justice is depicted, and the large dish in the Civic Library of Trento with a purple diaspartum background and a Byzantine-style frieze of vine leaves and clusters, flying birds, and peacocks.
For over three centuries, the Muranese glassmaking dynasties gave blown glass incomparable prestige with slender, graceful forms, applications of filigree leaves (in reticulated patterns), opalescences, engravings, and imitations of hard stones, as well as marbled glass or beads made from cutting polychrome glass rods used to form vessels known as millefiori. However, the most artistically evocative expression of 15th-century Italian glass is that of gold-glass with engravings, where the thin metal leaf was fixed with egg white and scratched with the point of a needle. The oldest work of this type is a very fine Madonna in the Civic Museum of Turin, attributed to Lorenzo Monaco, in which various colors appear beneath the engraving. Also in the 15th century, a characteristic production began in Germany and especially in Bohemia, where crystal glass, with brilliant reflections, suitable for cutting, became established. During the Baroque period, France, which had held supremacy in the 13th century with the masters of stained glass, developed, through the Parisian Lucas de Nehou (second half of the 17th century), the production of sheets by casting and lamination, and at the same time, lead crystal, known as flint glass, became fashionable in England. 18th-century production was dominated by the German factories of Nuremberg and Augsburg, with wheel and diamond-point engraving, and those of Bohemia, whose methods were adopted by Giuseppe Briati of Murano for his large mirrors, adorned with raised flowers. Industrial progress in the last century made the manufacture of glass objects mechanical and commonplace, and only in recent decades have the furnaces of Murano regained their prestige, applying traditional craftsmanship to the new decorative aesthetics.
As might be demonstrated by a glass vessel from the Catacomb of Callisto, in which, among other depictions, one is believed to represent the characteristic iconographic type of this Emperor. Similarly, one of the oldest specimens comes from the same catacomb, bearing the inscription "Potita propina." In general, archaeologists agree in attributing the gold-glass vessels to the 3rd century, especially the 4th.
The glass vessels are mostly bases of cups, whose figures or inscriptions were executed so that their right side corresponded to the inner part of the cup itself, to be more easily seen or read by the user. Their size varies, with the largest ranging from 8 to 10 cm or more; smaller ones measure about 3 cm. The inscriptions are almost always in Latin; Greek or Greek-Latin ones are not lacking; sometimes they show orthographic errors and letter substitutions (Critus - Zesus). According to some, the Christian-themed glass cups were used for the celebration of the Mass, or at least for the distribution of Communion, or finally for the agape meals above the martyrs' tombs. Regarding the Eucharistic use of glass, especially of patens (glass disks, not cup bases; noteworthy are the two patens known as the Cologne patens), in the 6th century the author of the Liber Pontificalis attributes to Pope Zephyrinus (199-217) the order to use glass patens during the celebration of the Mass, and writes that Pope Urban (222-30) prescribed the use of silver patens (Lib. Pont., I, p. 139, no. 3 and p. 143, no. 2). In conclusion, for the gold-bottomed cups, it can be said that they were used for every purpose of civil and family life, not only by Christians but also by pagans, as can be easily inferred from the varied subjects depicted on them: mythological (Achilles and Deidamia, the labors of Hercules, Minerva, Pluto, Serapis, Ceres, etc.), theatrical, athletic, hunting, domestic, rural scenes, and trades.
Placed over tombs, the cups suffered severe damage and destruction at the hands of cemetery plunderers, who broke them to sell the fragments, often leaving the base fixed in the plaster of the loculi. This practice is traced back even to early times, with accusations against the Jews, itinerant sellers, especially in Trastevere, who used broken glass for small trade exchanges, referring to a passage by Martial: "... transtiberinus ambulator / qui pallentia sulphurata ( = matches) fractis / permutat vitreis..." (Epigrams, I, 41 [ancient eds., 42], ll. 3-5), or even by Statius: "hic plebs scenica quique communitis / permutant vitreis gregale sulpur" (Silvae, I, 6).
Gold-glass vessels are important both from an archaeological standpoint and, in a special way, from an hagiographic one, because even those with Jewish subjects (temple, seven-branched candelabrum, Ark of the Covenant) are interpreted as symbols or figures of Christianity. They can be distinguished, according to the scenes, into biblical: Adam and Eve, Susanna, Joseph in the cistern, the bronze serpent, the return of the spies from Canaan, Joshua halting the sun, Moses, Daniel in the lions' den, the three young men in the furnace, the story of Jonah, Tobias, the sacrifice of Abraham, etc.; into properly hagiographic: the Good Shepherd, the Madonna, the saints Peter and Paul, often together with Christ, sometimes indicated by the X, the Evangelists, saints, popes, the saints Lawrence, Hippolytus, Timothy, Cyprian, Agnes, and others, in groups or individually; there are those with scenes from the New Testament: the Wedding at Cana, the Raising of Lazarus, Moses striking the rock, Peter striking the rock.
GLASS — Nuptial cup known as the Barovier cup, with the portraits of the spouses painted in enamel (15th century) — Murano, Glass Museum.
«PETRUS VIRGA PERQUOSED FONTEs CIperunt QUORERE»), Jesus or the Lamb upon the mountain, and others; those familiar ones: spouses clasping hands, with the inscription: *vivatis in Deo*; another example: *Martra Epectete vivatis*. Groups of parents with children: often with one, sometimes with two, rarely with more; notable is one with parents and four children.
In the graffiti inscriptions, the concept of drinking and living recurs almost always, often in Greek rendered with Latin letters: *bibe et propina, pie zeses, vivas cum parentibus tuis, pie zeses cum Donata, piete zesete - propinate, refrigeris in pace Dei, spes hilaris, zeses cum tuis, dignitas amicorum vivas cum tuis feliciter, hodor suavis*; or in Greek: ΠΙΕ ΖΗΣΑΙΣ ΕΝ ΑΦΑΟΙΣ, ΕΥΟΔΙ ΤΑΥΚΥΤΑΤΕ. ΖΗΣΑΙΣ ΑΝΙΜΑ ΒΟΝΑ, ΚΟΝΙΑΙΑ ΚΑΙ ΑΕΣΤΙΝΑ ΠΙΕ ΖΗΣΕ.
Important is the glass cup with deep engravings, depicting Christ with the monogrammed Cross and an open book in His right hand, flanked by a palm and a basket of loaves (4th–5th century), recently discovered in a house in ancient Ostia.