Arts of Glass

By Roderick Conway Morris

FLORENCE 26 June 2004

National Archeological Museum, Naples
The Blue Vase, from the House of the Columns, Pompeii, 1st century AD

Just as bronze sculpture from antiquity is rare in comparison with that made in stone, because the more expensive material was later ruthlessly recycled for other purposes, the fragility of glass has meant that only a tiny proportion of that produced in ancient times has survived.

This has had a distorting effect on our understanding of the revolutionary effect that the introduction of glass had on the Roman world and its role in the subsequent development of Western civilization.

Over the last few years, thanks to the coming together of experts in different fields, the history of glass has been reappraised. The benefits of this interdisciplinary approach are displayed in an engrossing exhibition, 'Vitrum: Glass Between Art and Science in the Roman World,' at the Palazzo Pitti. The show contains more than 400 pieces of ancient glass, some of extraordinary beauty and nearly all of exceptional interest; it continues until Oct. 31.

Glassmaking originated between 3000 and 2000 B.C. in Mesopotamia and spread to Egypt. But the most significant technological revolution occurred in the first century B.C. in the area of Syria and Palestine: glass blowing employing a tube. Almost overnight, glass became the most miraculously malleable, adaptable, multipurpose material, much like plastics transformed the 20th century. The Romans saw the potential almost immediately, and began to invest massively in its development.

Almost every technique and process employed in glassmaking today was adopted or experimented with by the Romans over a period of less than a century. The special Roman genius for organization and the peace established by the Augustan emperors led to the rapid diffusion of glass and of sites for its manufacture to the farthest corners of the empire. It has now been calculated that, by the second century, at least a million pieces of glass were being produced each year.

We are fortunate that some amazing examples of art glass have survived the vicissitudes of the centuries, such as the 'Blue Vase' on show here, an amphora decorated with figures, animals and foliage (it probably came from the same workshop as the British Museum's famous 'Portland Vase').

The exquisite finesse of these pieces has never been surpassed. But even more banal objects are admirable in their combination of design, aesthetic sense and practicality.

Nonetheless, for the average Roman, glass soon became not an art object but a fact of everyday life. As glass production became widespread, prices fell and glass tableware became no more expensive than that made in ceramic and cheaper metals. A study of household goods in a number of homes of different social type at Pompeii and Herculaneum has shown that humbler dwellings contained a similar number of glass utensils as those of their wealthier neighbors.

Thus, as was to happen with the reinvention of mass production of glass in the 19th century, the same jam jar, as it were, could be found in the larder of the lord and on the table of the agricultural laborer.

The great advantage of glass for drinking and eating from and for storing food in was that its inertness lent no flavor of its own, a quality praised by a number of ancient writers. Expensive wines that benefited from aging were kept in glass bottles. As Pliny the Elder wrote in the mid-first century: 'The use of glass containers has truly supplanted those made of gold and silver.'

Petronius in 'The Satyricon' relates a strange story of a glassmaker who has invented an unbreakable jug, which he demonstrates before Caesar by hurling it down on the marble floor and hitting it with a hammer, from which it emerges unscathed. On learning that the glassmaker is the sole repository of the secret of how to make it, Caesar orders that the man be put to death, since 'if this invention should become widely known, gold would become worth less than stones.'

Fanciful though this tale sounds, there is now evidence that the Romans did indeed produce toughened, 'unbreakable' glass by adding elements such as aluminum, and examples, although distorted by the intense heat of the volcanic eruption, have been found at Pompeii. (Archaeology has also turned up evidence of a full-blown Roman glass-recycling industry, which might also have been threatened by the new wonder product.)

No less surprising is the architectural section of the exhibition, which provides fascinating evidence for the wide employment of windowpanes, often of considerable dimensions, in houses and public buildings. Greenhouses with glass windows also seem to have been popular, the tougher and more translucent glass planes replacing the sheets of mica that the likes of the Emperor Tiberius used for his greenhouses on Capri to protect his cucumber plants.

Even double glazing was not unknown. Pagan Roman expertise in coloring glass panes paved the way for the great stained-glass windows of European Christendom. At the same time, the development of glass windowpanes coincided with the invention of glass mosaic, another means by which light and color was spread throughout the Roman and Byzantine worlds.

The implications of glass for medicine and science were no less far reaching and long lasting. The examination of urine was the primary medical diagnostic tool, and the invention of clear glass made it possible to carry out this investigation with new exactitude. Samples and medications could be kept in glass vessels without the risk of contamination.

For science in general, glass was put to a host of scientific uses, including magnifying glasses and prisms for studying the colors of the rainbow, and to watch chemical reactions and observe hydraulics. Indeed, many of the glass instruments here would still look perfectly at home in a modern laboratory.

Although they mastered almost every aspect of glass manufacture and use, the ancients never worked out the mechanism that created glass in the first place. To them it was a primary substance, like copper or lead, that was extractable from sand, just as metals could be drawn from rock, rather than the result of a chemical reaction. (Curiously enough, in English the term in art for glass in its molten form is still 'metal.')

The notion that you could obtain a valuable material like glass (used by the Romans to imitate precious stones) from a common and garden material, sand, undoubtedly encouraged alchemists in their belief that gold and silver could be made from base elements and encouraged their experiments to achieve this. So, even the ancients' misapprehensions about the origins of this miraculous substance helped lay the foundations of modern chemistry.

First published: International Herald Tribune