Rewriting the Book: Archaeology and Experimental Glass from the First British Colony in America

When the alchemist-priest Antonio Neri published his L’Arte Vetraria in 1612, the universe of codified knowledge could finally include a major work entirely devoted to glassmaking.[1] Although the Florentine friar was by no means the first to provide instructions on how to make glass (recipe texts are known from the second millennium BCE), never before had the effort been so comprehensive and successful.

Like many other collections of recipes, Neri’s manual was mostly concerned with the creation of colored glasses in imitation of gems and stones. A wide variety of reagents were used to achieve the different hues and levels of opacity, but only two ingredients were necessary to obtain plain glass, namely, a vitrifying agent of sand or quartz pebbles and a flux to lower the very high melting temperature of pure silica. The latter role had traditionally been played by vegetable ashes from forest, coastal, or desert plants, each resulting in glass with a different aspect and physicochemical properties. Direct availability often dictated the choice of flux. In the densely forested regions of Central and Northern Europe, glassmakers used inland plants such as beech, fern, or oak. Choice of flux could also be driven by the specific characteristics of the products desired. Thus, glass made in Venice and other Southern European centers contained ashes of plants imported from the Near East. The lower amount of impurities in these sodium-rich ashes made possible the production of the famous colorless cristallo.[2]

L’Arte Vetraria itself was an attempt to codify the kind of artisanal knowledge that Antonio Neri had been experiencing both by reading and by practice in the years before he wrote the book.[3] As the old proverb says, however, “there is more than one way to skin a cat.” Any attempt to codify artisanal knowledge would inevitably fail to cover the ample spectrum of possibilities that arise from the specific requirements or the particular choices of the individuals involved. Artisans did not always “play by the book.” In fact, they often did not even know there was a book. From our twenty-first-century vantage point, the information value of such handbooks and manuals is not under debate. Yet handbooks and manuals only tell part of the story of artisanal practices.

Recent research among historians of science shows that the more elusive part of the picture, the part that did not make it into books, can and should be looked for because of the role that artisans played in the development of scientific knowledge in early modern Europe.[4] The same historiography also proposes a way to study this development from the bottom up, starting with the experimental practices of virtually unknown people who seldom left behind any visible trace. Recognizing the limitation of manuals and handbooks and seeking to access the frequently uncodified (or less codified) knowledge that artisans possessed, some scholars have decided to turn their attention to alternative sources.[5]

Archaeology could be a potentially powerful ally in this quest, a suitable perspective from which to begin exploring the often implicit knowledge of artisans and their workshops. Archeology could offer a useful entry point into discourses around the concept of “learning by the book” and how the codification of knowledge relates to specific multifaceted microhistories. More specifically, archaeometry, the application of scientific techniques to analyze artifacts in archeology, is a valuable tool to extract relevant information from material culture because it tells us how a particular object was made, what went into a reaction vessel, or which steps were followed to achieve which end product. There are several cases of archaeological materials recovered from early modern contexts that can be of interest here, particularly the remains of workshops and chemical laboratories. The example that follows is one of them.

In 1608, around a year after Jamestown had been founded in what became Virginia, supply ships arrived filled with provisions and men to make the colony a profitable venture. Alongside apothecaries, goldsmiths, and refiners, there were glassmakers, the last specially recruited from Germany to establish a large-scale glass industry to boost England’s weak production. Unable to sustain increasing market demand, England had to import large quantities of the material. The unspoiled land of Virginia offered the chance to change this trend. We know from written accounts that the German glassmakers produced some glass, a sample of which was soon sent back to London as evidence, but nothing else is known about their work, at least not from written testimony.[6] On the other hand, an assemblage of ceramic crucibles has been recovered from the site, some of which chemical analysis indicates were used to make glass.[7] The glass attached inside the vessel walls was tested to obtain information about its technology of manufacture, and the results have proven somewhat surprising.

Although it is possible to observe a general tendency of Jamestown glassmakers to stick to the knowledge that must have been the most familiar to them (the forest glass of central Europe codified in technical treatises of the period), some aspects seem to diverge markedly. What is most unusual is that the analyses reveal the addition of an unexpected ingredient to the batch, crushed feldspar. This additive was completely alien to glass-making in Europe at the time. In any case, further investigation indicates that the feldspar was probably waste material from assayers operating nearby, who kept the metal-rich part of the mineral and discarded the unwanted sterile fraction.

The artifacts of Jamestown tell us a story of dialogue between crafts, where one’s by-product becomes another’s raw material. Still, one wonders why expert craftsmen would deviate from an established practice to enter the unknown. It is true, however, that the whole Virginia venture must have been a jump into the unfamiliar, into a world that had to be experienced to be understood. The technical knowledge learned through practice in German glasshouses was probably not completely transferable to the American land in the short time at their disposal. Some degree of adaptation was necessary. New species of plants and rocks were being discovered and settlers worked with them in the furnace to assess their quality. The first glass produced on the American continent was a European product and yet the new environment seems to have triggered a departure from tradition. Unfortunately, the rapid failure of the early industrial efforts caused by the innumerable difficulties encountered in the colony’s initial years makes it impossible to know whether this departure would have actually produced glass of good quality.

The story of Jamestown’s glass underlines the usefulness of integrating artifacts into the spectrum of sources we use when characterizing technical knowledge and investigating the codification of craft technique. The archaeological perspective offers a different angle from where to look at the history of learning. Unexpected results might arise from such a cross-disciplinary approach and discrepancies between textual and material documentation (codified knowledge and microhistories) are apt to throw fresh light on what we study.

Umberto Veronesi is a PhD student at the Institute of Archaeology, University College London.