Sara Vincx

Still life with façon de Venise wineglass,

Alexander Adriaenssen (1587-1661)

Antwerp.

In the 1590s, after the death of her husband, Sara Vincx ran a successful glassmaking business in the city of Antwerp. In the midst of a major war, she presided over a furnace where craftsmen from Murano, Italy made fine cristallo glassware for the elite families in Flanders. Vinx is the first documented female owner of a glass furnace anywhere.

The Dutch Eighty Years' War for independence from Spain was heating up in Flanders; towns were being pillaged and burned to the ground throughout the Low Countries. Even so, Vincx ably managed a crew of expert glass artists and brought her company's wares to market. When competitors tried to duplicate her products, she successfully defended her shop in court. Later, she remarried to Filippo Gridolfi, one of her foremen at the furnace. The two went on to open a show-room on the Meir, the most prestigious sales district of the city. They also welcomed glassmaker Antonio Neri to work at their facility. Neri was living in the city on an extended seven year visit to his friend and fellow alchemical experimenter Emmanuel Ximenes. 

The seven years that Antonio Neri spent in Antwerp were arguably the most formative for his knowledge of glassmaking. While his first exposure to the art was in Italy, a large portion of the skills and recipes exhibited in his recipe book, L'Arte Vetraria, trace to his activities in the Low Countries. Neri writes "This will make a beautiful aquamarine so nice and marvelous, that you will be astonished, as I have done many times in Flanders in the city of Antwerp to the marvel of all those that saw it." On tinting rock crystal: "In Antwerp, I made quite a bit of this, some ranged in tint from an opal color that looked very beautiful, to a girasol, similarly nice." On equipment: "In Antwerp, I built a furnace that held twenty glass-pots of various colors and when fired for twenty-four hours everything fused and purified." He also speaks of chalcedony glass, paste gems  and ultramarine paint all crafted in Antwerp.

Neri was apparently on good terms with Vincx and Gridolfi, perhaps he was introduced through Ximenes, one of the wealthiest men in the city. In his book Neri describes Gridolfi as "a most courteous gentleman." Vincx and Gridolfi possessed exclusive rights in the region to produce cristallo glass in the Venetian style (façon de Venice) a type of glass that Neri was already quite familiar with from his time making glass in Florence. The license, or patent as it was called, passed down from previous owners, was quite a valuable part of the operation. Employed in their shop was a steady stream of craftsmen from Murano. They made the finest glassware for the upper classes of Antwerp and surrounding areas. Because these craftsmen were bringing the secret techniques with them, they worked outside of the guild system, which would have otherwise required them to share their techniques with other artisans. Through special arrangements with the local authorities, the Venetians were exempt from joining. 


Sara Vincx (or Vincks) was the widow of the former owner, Ambrogio de Mongarda. Gridolfi had previously worked in the shop under Mongarda, who had been in the business for twenty years. Vincx was pressed into service by unhappy circumstances. In 1594, Ambrogio returned alone to Venice to recuperate from gout, but by the following year he was dead, leaving Sara to both run the glass shop and care for at least eight young children. Sara Vincx carries a distinction as the first documented female owner of a glass furnace anywhere. She took an active role in the business as attested by lawsuits she filed, and won, against rival shops that violated her patent. Records show she also expanded the furnace and hired two new artisans to increase production.

Despite the war and the blockade of the Scheldt River, which shut down trade by sea for a number of years in Antwerp, the glass furnace there thrived and reached its zenith under Vincx and Gridolfi. Soon after their marriage, seventeen employees were counted working at the shop. They established their own retail presence on the Meir, selling high-end cristallo within steps of the Ximenes palace. Their glass operation enjoyed top-rung status, and no doubt, Antonio Neri's involvement must have bolstered the reputation of the firm even further.

*This post first appeared here in a shorter form on 4 October 2013.

Women in Alchemy

Antonio Neri, 1598-1600,

MS Ferguson 67, f. 25r.

It is certain that women have participated in the practice of alchemy since its beginnings, but hard documentation is scant. Maria Prophetissima, also known as Mary the Jewess, is perhaps the best known female alchemist. None of her writings have survived, but she is thought to have lived around the third century. Legend tells that the "bain-marie" (double boiler) is named after her.

In the seventeenth century, celebrated glassmaker and alchemist Antonio Neri provides us with further detail, even if raising more questions than answers. One of his manuscripts, entitled Tesoro del Mondo (Treasure of the World) depicts three women running chemical equipment. Unfortunately, we are left to guess who they were and what role they played in the larger Florentine technical arts community. It is possible that these were nuns, trained in the same Church sponsored educational system that produced Neri. Convents were often expected to be self-sufficient and many ran their own pharmacies. Neri had sisters as well as brothers and at least one sister entered a convent located on the north side of Florence, near the laboratory where Antonio practiced alchemy and made glass. The fact that specific names have not been associated with Neri’s three female co-workers should not deter us from celebrating their contribution to the birth of early modern science.

Within a year of his ordination in the Catholic Church, Neri began an ambitious treatise, illustrated in his own hand, devoted to "all of alchemy." Six of the illustrations in this manuscript, completed in 1600, show women tending equipment. It is not remarkable that some alchemists of the 16th century were women, what is remarkable is to find them in the historical record. Direct depiction of female participation in alchemy is otherwise extremely rare. 


Two pictures in the Neri manuscript show female alchemists at

Antonio Neri, 1598-1600, 
MS Ferguson 67, f. 35r.

work. In both cases, the technician stands behind a dedicated piece of apparatus, facing forward, giving the impression of propriety in an arranged portrait. In other words, Neri is drawing his co-workers at their stations, practicing their art. The first drawing depicts a furnace and vessels used to make liquid mercury from its ore. The other shows a different type of furnace with a 'tower,' used as an efficient way to cook ceruse (white lead oxide). These images are part of a larger set of two dozen similar drawings that each illustrate the equipment used to prepare a specific product, many include a furnace and glassware. Nine of these show a single individual, (or in one case two men) tending the equipment. Because the manuscript is a recipe book, it contains almost no personal information. However, the context of these illustrations indicated that like their male counterparts, the individuals depicted all have specific responsibilities and specializations within the workplace.


Three other illustrations in the manuscript are notable for their engagement of women. These pictures show details of kitchen and nursing work; what might be termed more traditional female roles in the sixteenth century. Two of these illustrations are devoted to the respective arts of preparing plants and animals. They show women working alongside men performing various tasks. A third illustration shows medicinal fogging tents tended by a woman. Inside one tent, a male patient sits naked on a bench, exposed and breathing fumes pumped in by a large vessel perched over a fire. Similar arrangements are known to have been used to treat skin lesions caused by leprosy and syphilis.

Antonio Neri, 1598-1600, 
MS Ferguson 67, f. 37r.

The circumstances in these images present other possibilities to Antonio Neri's work environment. One is that the scenes take place at the Neri household on Borgo Pinti in Florence. Antonio's father was the personal physician to Ferdinando de' Medici, the grand duke of Tuscany. He was also the head of the college of physicians in Florence, and presumably ran a thriving private practice. The women may be Neri's siblings or other family members. 

Another possibility is that we may be looking at operations inside the Casino di San Marco soon after prince Don Antonio de' Medici's occupation of the facility. This palace laboratory had a reputation for medical cures that extended throughout Europe. Don Antonio spent extravagant sums to learn alchemical and medicinal secrets. The glass furnace here, which had employed masters from Venice is where Neri began formulating glass. The presence of women among his colleagues indicates a social setting with a camaraderie not displayed in other alchemical works of the period. 

* This post first appeared here on 17 March 2013 in a slightly different form.

Antonio Neri's Birthday

Relief portrait of Antonio Neri,

artist unknown, La Specola Museum,

Florence.

Glassmaker Antonio Neri was born in Florence, Italy on 29 February 1576. Because he was a "leap year baby" we celebrate the actual day of his birth only every fourth year. From his baptismal record, we know the exact time of birth: "three hours and 25 minutes past sunset." In terms of current timekeeping conventions, sunset occurred on that particular Thursday at about 6:15 pm CET (local time), so the big event happened at 9:40 pm.

It might seem a bit odd to have such accurate records -- almost as if an astronomical event were being recorded. Actually, that is exactly what was being done; astrology of the sixteenth century drew a strong correspondence between 'macroscopic' events in the heavens and more earthly matters. To have an exact time of birth was seen as a way to gain greater insights into the events of ones personal life and to plan in a way that was more in harmony with the natural order of things.

Of all the days to be born, 29 February was considered among the least auspicious. A dire Northern Italian folk proverb states "An bisesti, o la mama o 'l bambi" predicting that, born on this day, a child or its mother was fated to die by year's end. Indeed, the Italian word naming the day, bisestile, had become a synonym for misfortune or calamity and is still the case for the French cognate bissêtre. Whatever stock the family put into ancient superstitions, happily this prophecy did not come true for Dianora or her fourth child Antonio.

Although his was a February birth, it was perhaps not as deep into winter as one might assume. Due to a discrepancy in the Julian calendar, which was in force then, the Spring equinox of Neri's birth year happened much earlier in the calendar than today, around 10 March, in fact. 

Infant mortality was not uncommon and for a child to die unbaptized only magnified a family's trauma. Church theologians had debated since the fourth century on the fate of the souls of such children. Most Catholic families baptized infants as soon as humanly possible, in Antonio's case the very next morning. Births occurring within Florence were officially registered at a central baptistery, San Giovanni, the ancient octagonal basilica standing directly in front of Florence's main Cathedral. 

The full baptistery record, in translation, for Antonio Neri reads:

Thursday, 1 March 1575:  Antonio Lodovico was born to Mr. Neri di Jacopo and Dianora di Francesco Parenti, residents of San Pier Maggiore parish. The time of birth was 29 February, at 3 hours 25 minutes past sunset. The godparents are Francesco di Girolamo Lenzoni and Ginevra di Federigo Sassetti.

The year is recorded as 1575 because in those days, Florentines celebrated the New Year on 25 March. Today we consider January, February and March to be part of the new year. 

Antonio joined a growing family that already contained siblings Lessandra, Jacopo and Francesco, and later would number ten children.  His father was thirty-six year-old Neri di Jacopo Neri, (Neri Neri to his friends) and his mother was twenty-one year-old Dianora Parenti. Neri Neri was a prominent doctor and later was appointed to be the personal physician to Grand Duke Ferdinando. Dianora was the daughter of Francesco Parenti, Michelangelo's lawyer. 

Tradition dictated that births were celebrated with a house party open to friends and neighbors. Thirty-four year-old Francesco Lenzoni, Antonio's godfather, would certainly have done his best to attend. His family included Florentine senators and Francesco himself would later become Tuscan ambassador to Spain. Godmother Ginevra Sassetti, in her late fifties, was also from a prominent family. Her nephew Filippo would send plant specimens back from India to be inspected by Neri Neri and their mutual friend Baccio Valori who would become director of the Laurentian Library in Florence.

Antonio Neri, would go on to learn the finer points of alchemy and glassmaking, developing new formulas and techniques that would be applied throughout Europe. In 1612, he published the world's first book entirely devoted to formulating glass, L'Arte Vetraria. It seems especially appropriate that we pause and raise a toast (in glass, of course) to his accomplishment and to the end of February, looking forward to warmer days ahead. Buon compleanno Antonio!

Botanical Gardens

Rudolf  II as "Vertumnus"(c. 1590)

Giuseppe Arcimboldo.

In 1543-44 new botanical gardens were founded in Pisa; L’Orto Botanico was its Italian name. It was the very first garden devoted to the research of plants. Literally within a year, similar gardens sprung up in Padua and Florence, and many other cities followed shortly thereafter. Exotic foreign species as well as important local plants were grown, studied, harvested distilled, and imbibed. These horticultural stations became centerpieces of medical programs throughout Italy, and then greater Europe. The concept of herbal (“simples”) gardens was centuries old. Almost every monastery, convent and hospital maintained a space to grow the plants they needed to transform into medicines for care of the infirmed. The grafting of fruit trees was actively practiced since before Roman times, but these new gardens were specifically planted as research spaces and run by universities. 

When Neri Neri, the father of glassmaker Antonio Neri, studied medicine at the Studio Fiorentino  in the mid 1550s, there can be no doubt he spent time at the gardens in Florence, and quite possibly at the ones in Pisa. (The Pisa gardens were moved twice before arriving at their current location in 1591). This was a period of vigorous expansion in the field of herbal medicine. Competition was fierce to obtain and study medicinal plants from around the globe. Cosimo I de’ Medici poured money into the medical school in Pisa, attracting students and faculty from around Europe. In 1554 famed botanist and physician Andrea Cesalpino took over the Pisa gardens  from his teacher, Luca Ghini, who first built them. 

In 1602, Neri was to be found working alongside Niccolò Sisti at the grand duke’s secondary glass furnace along the Arno River in Pisa. According to Neri’s own account, Pisa is where he worked on ferns as an alternative plant salt for glass and mentions many other plants with which he experimented: 

Set about making ash in the way previously described, however use the husks and stalks of broad beans after the farmhands have thrashed and shelled them. The same may be made from the ashes of cabbages, or a thorn bush that bears small fruit, called the blackberry, even from millet, rush, marsh reeds, and from many other plants that will relinquish their salt.

In a letter to Neri from his friend Emanuel Ximenes, the Antwerp based Portuguese banker expressed surprise that Neri was able to devise a fern based glass salt recipe so quickly. In all likelihood, Neri would have had access to the botanical gardens and the small adjacent laboratory located just a few blocks from the glass furnace. In the period of time the glassmaker spent there, the directorate of the gardens changed hands from Francesco Malocchi to Marco Cornacchini. Both of these men avidly pursued new botanical based cures, and corresponded internationally. 

In his Glassmaking book, L’Arte Vetraria, Neri devotes a number of recipes to making paint pigments from flower blossoms. While he could have easily obtained his stock material from any number of sources, the botanical gardens would have certainly provided a convenient cache of many different varieties.

In the winter of 1603-4 Neri traveled From Pisa to visit his friend in Antwerp. If he followed Ximenes suggested route, he would have passed back through his native Florence, then on to Venice where he would meet up with a caravan of merchants on their way to the Frankfort spring fair, and then on to Antwerp by river. Upon his return to Italy, seven years later, he wrote his glassmaking book, but then devoted himself fully to alchemy and medicine. In January of 1614, in what might be the very last manuscript he worked on before his death, he wrote about some recipes “copied from an old book here in Pisa.” At that time, the director of the botanical gardens was Domenico Vigna, who continued to direct the gardens on and off until 1634.

It would be interesting to know how Neri the alchemist thought about his raw materials. Did he see all the possibilities of what could be made with them? For instance, how did he approach a towering pile of May ferns, large enough to produce a hundred pounds of ash, or a giant sack of rose petals? Did he ever lean forward and breathe in the delicious musty aroma? Did he ever dig in with his hands and bury his face in an arm-load of soft, pure color? How could he not?

*This post first appeared here 22 Jan 2014.

The Duke's Mouthwash

Ferdinando de’ Medici (1549-1609),

Scipione Pulzone (1544 - 1598), Private collection.

Antonio Neri's father, Neri Neri, was royal physician to the family of Grand Duke Ferdinando de' Medici. As such, he regularly interacted with other members of court, ranging from the archbishop of Florence, to his colleagues in medicine, including the royal apothecary (speziale), Stefano Rosselli. Rosselli shared more than a professional relationship with Neri Neri. They both admired the work of an ancient Greek physician named Dioscorides; Rosselli was something of an authority on his methods. In addition, he ran the 'Speziale al Giglio' shop, once owned by Tommaso del Giglio, who's chapel Neri Neri took over at Cestello church. Rosselli's son, Francesco, and Neri Neri were among the four chosen to revise and update the famed Ricettario Fiorentino,[1] the official reference for medicinal cures in Tuscany. 

On 21 September 1589, Rosselli started to compile his own book of recipes to pass down to his two sons, Francesco and Vincenzo, who would go on to continue the pharmacy.[2] The book begins with a poison remedy credited to none other than Cosimo de' Medici. Recipe no. 9 is the grand duke’s antispasmodic oil, presented by Niccolò Sisti, with whom Antonio Neri would later work at the glass house in Pisa. No. 20 is the duke's oil for deafness, also presented by Sisti. No. 41 is a poison antidote revealed to Francesco de' Medici by the Archduke of Austria. It was tested on a prisoner at the Bargello prison, a "volunteer" who was intentionally poisoned as part of the experiment, then revived with the antidote in the presence of Stefano Rosselli and Baccio Baldini, the long time physician to Cosimo I. Supposedly, the prisoner's reward for surviving was early release.

Recipe No. 30 carries perhaps a bit less risk; it is titled "Acqua da gengie di messer Nerj Nerj" (Mouth wash of Neri Neri):

Take a quarter of a bushel of mastic buds,a quarter of a bushel of myrtle buds, a quarter of a bushel of red roses, three ounces of alum, a half ounce of salt and a quarter ounce of hard rose honey. Mash the herbs with a mortar and pestle and put them in nine pounds of Greek wine for twenty-four hours, then boil in a bain-marie and reduce to two-thirds. In this, we bathe the gums: it makes them dry and firm.

Mastic: Pistacia lentiscus. Native to the Mediterranean, its resin used for millennia to settle upset stomachs.
Myrtle: Myrtus communis. An Aromatic herb used by the ancients, effective treatment for sinusitis.
Alum: Used by the ancients as a treatment for canker sores.
Rose Honey: Miele rosato. Honey infused with rose petals, an astringent still used to sooth children’s teething pains. It is produced both as a solid and a liquid. 
Greek Wine: Vino Greco. Italian wine made in the style of sweet Greek wines. In 1673, English botanist John Ray describes it as being made from grapes grown on the slopes of Mount Vesuvius.

The date that Stefano Rosselli started his book of secrets is interesting because it is the same day that Neri Neri, with the grand duke's two other physicians, Cini and Da Barga, were busy making medicinal wine based on Dioscorides' ancient recipes. Perhaps they all met that day at Rosselli's shop, for his advice. 

[1] Neri, Benadù, Rosselli, Galletti 1597.
[2] Rosselli 1996; an Italian transcription and French translation of Rosselli's recipes, with a very entertaining introduction.

* This post first appeared here on 4 November 2013 in a shorter form.

The Duke's Oil

Trajan's Column, Rome

Giovanni Battista Piranesi (1758)

In the seventeenth century, alchemy was a dangerous business. Yes, there were risks of sanctions by the authorities, which could be very harsh, but great dangers also lurked in the chemicals themselves. Some like lead and mercury accumulated in the tissues slowly, over a period of years, others could kill a man within a few minutes. Cardinal Francesco Maria del Monte had personal knowledge of just how deadly the products of alchemy could be.

In Rome, Del Monte was the unofficial ambassador to Florence and the Medici family. He regularly greeted dignitaries from around Europe and dazzled them in his sumptuous palace. He was an avid glass collector, a patron of the arts and more quietly a dedicated student of alchemy. He was a lifelong friend to Don Antonio de' Medici and visited the prince's laboratory in Florence several times. This is where Antonio Neri was making glass early in his career. Later, Neri worked at a secondary Medici glass furnace in Pisa, where the cardinal had fancy glass table service made for the Vatican.

About a two mile walk from Saint Peter's Basilica, over the Tiber River, directly toward the Colosseum, is Trajan's Column. It commemorates Emperor Trajan's victory in the Dacian Wars at the beginning of the second century. It displays a scroll in base relief that winds all the way from the pedestal to the capital. The monument is large enough to contain an internal staircase leading to an observation platform at the top. In 1587, it was crowned by a bronze statue of Saint Peter that still stands today; the initial model was sculpted by artist Tommaso della Porta, who was under the patronage of Cardinal Del Monte. 

Giovanni Baglione picks up the story in his book Lives of Painters, Sculptors and Architects:

That man [della Porta], I think, suffered mentally and it showed at the end of his days. When he felt some kind of tingling in his abdomen, he went to the Cardinal del Monte his friend and master and asked for some of the "grand duke’s oil" that he hoped would relieve the tingling. The Cardinal indulged him; gave it to him and said that he should apply it only to the wrists and only a little, because the oil was potent and it could make him feel sick. He took it and went back to his house and after dinner he sent for the barber, to administer the medication, and while the messenger went on, Tommaso impatient and simpleminded, applied the oil himself and instead of touching the wrists, as the Cardinal had instructed, he lathered the arms, chest, body and entire abdomen, so that the powerful oil went to the heart and in fact killed him. The barber arrived to medicate him, found him dead and all attempts at revival were in vain. Tommaso della Porta, was buried at Santa Maria del Popolo.

The "grand duke's oil," was widely known, and widely cited in references throughout Europe well into the 19th century. Its other name was oil of tobacco – essentially a distillation of almost pure nicotine. In very small doses, it acts as a stimulant of the central nervous system, in slightly higher doses it is a narcotic, even greater, but still relatively small amounts act as a quick and lethal poison absorbed directly through the skin. Ingesting a single pill capsule of typical size full of pure liquid nicotine is more than enough to kill an adult in short order.

This story has one final twist. Antiques dealer Domenico Lupo was one of the men present at the reading of Della Porta's will on 7 March 1607. Twenty-five years later, an inventory of Lupo's assets listed a "small figure half old and half new that is said to be of Prior Ant. Neri," either the glassmaker or possibly his great uncle. 

* This post first appeared here 5 February 2014. 

Glass or Rock?

Rock crystal ewer, Egypt (1000-1050)

V&A Museum, #7904-1862

Today, a sharp distinction is made between glass and rock, but in the early seventeenth century, differences in the two materials were not so well defined. One was the product of nature and the other of art, but after that the lines begin to blur. Philosophers debated whether glass should be classified as artificial stone, and why not? It is a material that was actually made from crushed up rocks (quartz and calcined limestone) with the addition of plant salts. In a very accurate sense, it is a form of artificial rock. 

In his 1612 book L'Arte Vetraria, Florentine glassmaker Antonio Neri repeatedly illustrates the thinking that glass was an artificial form of rock. The very first part of the book concerns itself with cristallo glass, which was considered to be an imitation of natural rock crystal. He devotes a whole section to the imitation of the colorful stones variously known as chalcedony, jasper and oriental agate. About these he writes: 

It is often said, and it may well seem to be true, that art cannot match nature. However, experience in many things shows, and this is particularly true of colors in glass, that art not only challenges and matches nature, but by far exceeds and surpasses it. Why, if you did not see it for yourself, you would find it hard to believe the beauty and great variety of interplay seen in these particular chalcedonies.

Another entire section of the book is devoted to artificial gemstones: rubies, sapphires, emeralds, topaz, chrysolite; he even uses crushed natural gems to color his glass. He describes a "sky blue even more beautiful, from the garnets of Bohemia." 

An earlier 1540 book that Neri read closely was by Italian metallurgist Vannoccio Biringuccio, called De La Pirotechnia. This was the first book entirely devoted to mining and metal foundry practices. Biringuccio was from Siena, but was considered something of a folk hero in Neri’s nearby Florence because he oversaw the casting of iron cannons for the city's defense in the great siege of 1529–30. His book contains a short six-page chapter devoted to glass where he writes:

[I]t [glass] is one of the effects and real fruits of the art of fire, because every product found in the interior of the earth is either stone, metal or one of the semi-minerals. Glass is seen to resemble all of them, although in all respects it depends on art.

This is an observation that Neri echoes almost verbatim in the introduction of his own book, and in this light, it is not so difficult to see what connects glassmaking to alchemy. Neri was in the business of learning nature's secrets, and then using them to create new materials that were even better than the originals. These are aims quite familiar to any modern materials engineer. Neri and his contemporaries were successful up to a point. They were able to create artificial gems and other items that were impressive in color and clarity, yet they lacked some key properties of their natural counterparts, most notably hardness. 

Based on Neri's earliest known writing Treasure of the World, started in 1598, he was already familiar with mining practices before his glassmaking activities started and over a decade before he would write the book. He devotes this early manuscript to "all of alchemy, its furnaces, instruments and the mining of metals." Around 1600 he started work at Prince Don Antonio de' Medici's Casino di San Marco laboratory. Here, he may have had the opportunity to interact with characters such as Filippo Talducci (1543- c.1615), celebrated Florentine chemist and mining engineer, several of whose relatives worked at the Casino. In his 1613 manuscript Discorso, Neri strongly hints that he has personally been to more than one mine in connection with his alchemical activities. "I would not say this, had I myself not had the good fortune of being in such a mine from which, with much artifice, was extracted a small quantity of real gold liquor, which was the true golden seed. […] To this day I have never found another mine like it, and therefore suitable for this purpose."

Today, we hardly associate glass with the raw materials from which it is composed, just as we hardly ever think of metals in their unrefined state. Antonio Neri was more closely connected to the earth, by virtue of his profession, but also because daily life in the early seventeenth century was filled with such activity; refining raw materials into useful forms had a direct and immediate impact on quality of life. Although glass is now manufactured in highly automated facilities, far away from our daily lives, it is still essentially the same product that Neri made. The next time you come in contact with a piece of glass, to pour a drink or look through a window or read the text on a screen as you are probably doing right now, stop for a minute and think of it as Neri did four centuries ago, as artificial rock.

* This post first appeared here 17 Feb 2014.