Don Giovanni in Flanders

 

Spanish attack on a Flemish village,

Attr:  Pieter Snayers. (click to enlarge)

In the winter of 1603-04, Glassmaker Antonio Neri embarked on what would become a seven-year-long visit to Antwerp, possibly the most productive period of his career. He was to stay with his Portuguese friend, Emmanuel Ximenes, one of the richest men in that city. But Neri was not the only Florentine courtier in Antwerp; Don Giovanni de' Medici, Florence's top military commander was already there, prosecuting a war. He was uncle and friend to Neri's sponsor Don Antonio, as well as an alchemist in his own right. There is no known record of a meeting, but it is not hard to imagine Giovanni as a dinner guest at the Ximenes household.


Neri had moved from the safety of the Tuscan hills into the very center of a bloody war for Dutch independence. The Dutch wanted freedom from Spain, which was allied with the Holy Roman Empire through a single ruling family: the Habsburgs. Within the previous thirty years, Antwerp had been burned and pillaged by Spanish soldiers that had gone unpaid by their employer. The carnage cemented a regional rebellion that would last for most of a century. The so-called "Low Countries" were divided by religious lines into the Protestant "North", and the Catholic "South". The northern territory, known as the Dutch Republic, had seceded from Hapsburg rule in 1581. As Neri started his journey in late 1603, the southern territory, Flanders, was caught in the middle between warring factions. The North had become a haven for protestant Calvinists and Lutherans who streamed in from surrounding countries. In the South, Catholic Antwerp was near the center of the conflict. The city was blocked from sea-trade by their Dutch neighbors. Armed confrontations with imperial Habsburg forces demolished surrounding towns; fighting threatened to spill into the city that Neri would call home for the better part of a decade.

The troops on both sides of this conflict were not monolithic armies, but patchworks of borrowed forces and paid mercenaries. On the imperial side, an early attempt to break the blockade had been under the command of Don Giovanni de' Medici on behalf of his half-brother, Tuscan Grand Duke Ferdinando. Florence owed its allegiance to the Habsburgs. Don Giovanni was anxious to secure Catholic Flanders for Spain and secure a military success for himself. However, in truth, the situation was more nuanced. The Medici were privately sympathetic to the Dutch cause. They were friendly with the French Bourbons as well as the English who were both secretly financing the Dutch resistance, neither of whom wanted to see a strong imperial presence in the Low Lands. Flemish Catholics themselves lost no love for their Spanish overlords, who had already destroyed Antwerp once. Furthermore, trade and commerce continued between the North and South even if sometimes rather covertly. In 1604, Don Giovanni was back to help prosecute the siege of Ostend, under Don Ambrogio Spinola. This was a conflict so bloody that it ultimately leveled that city and took the lives of thirty-five thousand men. Ostend was the last remaining stronghold of the Dutch on the North Sea coast between Sluys and Nieuport. It was only sixty miles (95km) west of Antwerp.

As bloody as it was, war in the seventeenth century followed the seasons. In the winter, Don Giovanni found time to submit a design for the Chapel of Princes in Florence. He also had Flemish marble cut for the project, and shipped back to Tuscany using, yes, Dutch traders in Amsterdam. During the lull in fighting, at the behest of Grand Duke Ferdinando he commissioned paintings of famous contemporary battle scenes by Flemish masters, which were also shipped back to Florence on Dutch ships. One set of seventeen pictures, fully paid for by the Ximenes family, was destined to hang in the new Medici villa 'La Ferdinanda' at Artemino in Prato. The interior decoration of the public spaces in this villa were being executed by artists Passignano and Poccetti, fresh from their recently completed collaborative masterpieces; the Neri Chapel and Cestello church on Borgo Pinti, financed by Antonio Neri's father. After some delay, the paintings finally shipped to the Tuscan port of Livorno, in April of 1604, just as Antonio Neri was settling into his new quarters on the most fashionable street in all of Antwerp; the Meir.

By June of 1605, fighting was on Antwerp’s doorstep, Don Giovanni de' Medici was dispatched to London. He saw the King (James I) several times, but the reception was somewhat less enthusiastic than he had hoped (at least according to reports sent home by the Venetian ambassador). Three weeks later Giovanni left for Paris with the promise of a British royal ship to bring him across from Dover to Calais. Finding no such escort, he commissioned a Dutch captain for the voyage.  

Don Giovanni's behavior, at first blush, seems quite odd; perhaps even treasonous. Commanding troops under the Spanish flag, he left the front lines at Antwerp. Using enemy (Dutch) transportation, he traveled first to the English and then the French royal court, both powers recently at war with Spain and both sympathetic to the Dutch. However, Giovanni was in constant contact with Grand Duke Ferdinando and undoubtedly acted on direct instructions. While technically subjects of the Spanish crown, the Tuscan duchy had close economic and strategic ties with all the countries involved and had every reason to pursue a diplomatic solution that would avoid another bloodbath in Antwerp. A few years earlier, Giovanni had successfully stalled the Spanish infantry from a potentially devastating invasion of France and had military experience in the Low Countries that spanned two decades. Historically, Giovanni's part in any diplomatic negotiations has not been established, but within two years, a temporary truce was reached that would eventually result in Dutch independence. In April of 1607, a temporary eight month ceasefire was negotiated, which was later extended to cover conflicts at sea. For all intents and purposes, the war was winding down.

Sulfur of Saturn

 

The Roman Goddess Ops, 'sweet'-heart (and wife)

of Saturn, Peter Paul Rubens c. 1630,

“Abundance (Abundantia).” [1]

Antonio Neri’s 1612 book on glassmaking, L'Arte Vetraria, devotes an entire chapter to making artificial gems. These are made with an especially dense, refractive form of lead glass—what today would be called lead crystal. He made it in small batches, in sealed ceramic vessels; each infused with various metal oxide pigments to give characteristic jewel tone colors.  His secret ingredient for making the finest artificial gems was a material known as "sulfur of Saturn." He writes:

You will have jewels of marvelous beauty in every color, which by far surpass those described above, made with ordinary minium. Because with this true sulfur of Saturn, they will surpass all others by far more than I can write here, as I have seen and made many times in Antwerp.[2]

This "ordinary minium" that he speaks of is one of several oxide forms of lead, also known as 'red lead,' it is bright red or orange in color. As a stable red pigment it was well known to ancient Byzantine and Persian illuminators. [3] It was so popular, in fact, that the word used to describe small intricate pictures 'miniature,' is derived directly from 'minium.' [4] The intricate embellishments in manuscripts ultimately took on the name of the scribes' favorite color.  In glass, minium does not impart red or any other color on its own, but does add 'sparkle' and made Neri's jewels highly refractive to light. 

In the recipe, he uses white vinegar and he reacts it with finely ground minium through a laborious process. The acetic acid in vinegar chemically combines with the minium to form lead acetate, which alchemists called "sugar of Saturn" because it had a distinctively sweet taste (more on that later). [5] Lead (Saturn) could be added to the melt in a number of different forms including acetate, carbonate and various oxides. The heat of the furnace reduces them all and the result is essentially identical glass from any of these sources. The lead acetate has one major advantage that set it apart from the others. Lead acetate is soluble in water and therefore it can easily be purified of contaminants and to a much higher degree. It can be filtered, allowed to stand and decanted after any insoluble impurities settle out.

In other references "sugar of Saturn" and "sulfur of Saturn" are considered synonyms. This is not the case with Neri, for him they are two different substances; the 'sugar' is a precursor for his final product, sulfur of Saturn:

Left in the bottom will be a salt as white as snow, and as sweet as sugar. Repeat the dissolution, and filtering, and evaporation with common water three times. This is the required sugar of Saturn. 

Keep it to calcine in sand in a glass flask or ball in a furnace over a moderated fire for many days. It will further calcine to a color that is much redder than cinnabar, and more finely impalpable than sifted grain flour. This is the required true sulfur of Saturn; purified from the sediment, foulness and blackness that were upon the lead at first. [6]

It would be a reasonable guess that by heating the acetate for "many days" he is reducing it back to minium, its more basic, bright red oxide state, but this time in a greatly purified form.

Unfortunately for his health, in this recipe for sulfur of Saturn, Antonio makes extensive use of heating and evaporation. Even more unfortunate is that in a number of steps he judges the potency of his product by taste. Lead acetate is highly toxic; because it is soluble in water, it enters the bloodstream easily. It attacks the nervous system, accumulates in the bones and can cause organ failure. It is quite likely that by breathing the fumes and tasting crystals of sugar of Saturn, Neri was contributing to his own demise at the relatively young age of thirty-eight. Lead acetate was not the only toxic substance he handled regularly, but it was certainly one of the worst for his health. 

 It does not follow that he was totally ignorant of the risks he was taking. The dangers of heavy metals were recognized from early times. Pliny speaks of the noxious fumes from lead furnaces, and Plutarch opined that lead and mercury mines were "unwholesome and pestilent places." Neri’s own father followed the work of Dioscorides, who wrote that ceruse (lead carbonate), taken internally, could be fatal and that as a sweetener for wines could adversely affect the abdomen and the nerves.

Ancient Romans discovered that when wine started to turn to vinegar, it could be boiled down in lead lined pots to produce a highly sweet syrup called sapa. A late Roman cookbook made extensive use of sapa, which presumably contained considerable lead acetate. [7] It has been conjectured that  lead laced sapa contributed to poisoning among the Roman aristocracy. While lead acetate is a deadly poison, it may be a step too far to imply that it contributed to the fall of the Roman Empire.

[1] Alchemical tradition does provide for an association between the metal lead and the Roman god Saturn. However, there is no such association between 'sugar of Saturn' and either of his consorts Ops or Lua, although Ops, the goddess of abundance (opulence) does rather nicely represent the chemical that made Neri's most opulent artificial gems possible.
[2] Neri 1612, ch. 91.
[3] Chemically, this is Pb3O4, also known as Lead (II,IV) oxide, triplumbic tetroxide. Historically, it was called minium and red lead.
[4] The accepted etymology of ‘miniature’ is from ‘minium,’ but may have been influenced by similar Latin terms such as  minor, minimus, minutus, etc.
[5] Lead acetate comes in two forms; Pb (C2H3O2)4 and Pb (C2H3O2)2, both are toxic; the later variety is soluble in water.
[6] Neri 1612, ch. 91.
[7] “Saba” endures today as a popular grape syrup, albeit without the lead.
* This post forst appeared here on 12 September 2014.

Paste Gems

Pastes (glass) set in silver openwork (Portugal c. 1750)

Victoria and Albert Museum, London.

Acq. nr. M.68-1962

In many ways, the story of artificial gems traces the story of glass technology itself. From ancient times, when glass could only be produced in very small quantities it was regarded and used as a type of stone that was made through art. Alchemists thought the bright colors produced by metallic pigments in glass were a key to the philosopher's stone, and the transmutation of base metals into gold. As the technical prowess of glassmakers expanded, so did the ability to simulate specific stones, most notably coveted gems. Glass went on to be used as material for utilitarian objects like goblets and as an indispensable part of scientific enquiry. All the while, artificial gems have continued to dazzle us with their beauty. 

In the fifth part of Antonio Neri's 1612 book, he teaches the secrets of making artificial gems "of so much grace, and beauty, that they will surpass the natural stones in everything except hardness." It is not a difficult argument to make that this section alone is responsible for much of the lasting popularity of L'Arte Vetraria. It is easy to see why enterprising artisans would want to make glass imitations that could pass for the real thing. It is also perhaps tempting to jump to the conclusion that Neri intended his recipes to be used in deception, but there is no evidence whatsoever that this was the case.

Neri gives full credit for his innovative methods in paste gems to Dutch alchemist Isaac Hollandus. Hollandus is an enigmatic figure, whose writings survive, but not much is known of the man, his family, or even if he was living in Neri's time. What is known is that Antonio's dear friend Emmanuel Ximenes was the brother-in-law to Baron Simon Rodriguez d'Evora, a famous diamond dealer and jeweler of choice to royalty throughout Europe. He lived and worked on the same street in Antwerp as Ximenes' palace, only a few steps away from Neri's new temporary home. It was a common request of wealthy patrons to have duplicate jewelry made in paste for travel and security reasons. If a fake necklace or jewel could pass for the real thing, it was well worth the added expense, when the genuine article could remain safe under lock and key.

No artificial gem recipes have ever been found among Hollandus' writings, excepting one for ruby which is then crushed up as part of a prescription for the philosopher's stone. It is quite possible that Neri was applying a more general technique from the Dutchman. The basic material for all of Neri's paste gems is a fine lead crystal. The crux of his innovation lay in the form of lead used. Normally, metallic lead sheet was cut into small pieces, and roasted in a kiln such that it would oxidize into powder, but not melt. The powder was then added to the glass melt. In Neri's method the lead was chemically converted into a water-soluble form, which could then be filtered and purified to a much greater extent. The end result was a far better grade of crystal.

In 1697, Jean Haudicquer de Blancourt translated into French and greatly expanded Christopher Merrett's English edition of Neri. Blancourt gave no credit to the Italian for his work, and two years later, when it was translated back into English by Daniel Brown, the connection to Neri was completely lost, but the credit for paste gems remained with Hollandus. In the eighteenth and nineteenth centuries, numerous general encyclopedias of art and craft were published and the so-called 'Hollandus' paste gem recipes turned up many times. Meanwhile, a properly credited French version of L'Arte Vetraria was completed by Holbach in 1752. This edition was more suited to a scientific audience; he faithfully translated the Italian, but also incorporated the full comments of Merrett as well as those of Kunckel who issued his famous German version of Neri in 1679.

For more reading on Neri's artificial gems see Glass as Pasta and on the work of later investigators see Marieke Hendriksen at The Medicine Chest

Isaac Hollandus

 

J. Hollandus,
Chymische Schriften, (Vienna: 1773)

In early 1603, Glassmaker Antonio Neri traveled from Italy to Flanders, to visit his friend Emmanuel Ximenes. Neri would stay for seven years and in that time he worked on a number of glass related projects including the manufacture of artificial gems using lead crystal glass. An enduring mystery is that in his 1612 glass book L'Arte Vetraria, he gives credit to alchemist Isaac Hollandus for a "new chemical method never before used," yet no such recipe for artificial gems has ever been found in the writings of Hollandus.

Neri’s host, Emmanuel Ximenes, owned several titles by this somewhat obscure figure. Historians conjecture that there were actually two alchemists in the Hollandus family, Isaac and Johannes Isaac. Their relationship is not clear, although they are often assumed to be father and son. We know little about them; some authors date them as early as the fourteenth century. However, a preponderance of evidence point to about the time Neri lived. In his glass book, in the fifth part devoted to artificial gems, Neri writes:

Above all is this wonderful invention. A new way practiced by me, with the doctrine taken from Isaac Hollandus, in which paste jewels of so much grace, beauty and perfection are made, that they seem nearly impossible to describe and hard to believe.

A perusal of the literature of the time starts to put things into focus. In the 1679 German edition of Neri's L'Arte Vetraria, Johannes Kunckel tells us that Isaac was dead before Neri came to Antwerp. In his translation he adds his own parenthetical expression to Neri's words, "This is the manner to imitate precious stones of Isaac Hollandus, (namely, from his posthumous writings) that I learned in Flanders." And there is more; coinciding with Neri's visit, playwright Ben Jonson who had just returned to London from the war in Flanders, referenced the pair of alchemists in his satirical work which is, in fact, called The Alchemist (1610). In the play dialogue he says that the elder Hollandus was then dead but survived by "living Isaac." In 1644, the famous Flemish chemist Van Helmont identified Isaac Hollandus as a recent contemporary. In a 1716 treatise, Kunckel paid Hollandus a great compliment and at the same time took a swipe at Helmont saying "and the incomparable Hollandus had more of the fire-art in his little finger as Helmont in his whole body." In another reference, Sir Francis Bacon mentions Hollandus as "by far the greater part of the crowd of chemists." Even if these passages contradict each other on some points, here we have Kunckel, Jonson, and Bacon -- all respected luminaries of their time -- paying tribute to this very interesting pair of experimenters.

Now, we might also ask about the actual recipe that Neri was using. We have his version, but what about the original by Hollandus? It is an important historical question because Neri's version went on to be reprinted, copied, and plagiarized possibly more than any other glass related technical recipe in the 17th, 18th, and 19th centuries. One Hollandus title in Ximenes' Antwerp library was Opera Mineralia, first published in 1600. The subject of this volume is the philosopher's stone and its production. While there are no artificial gem recipes here per se, there are some intriguing connections between artificial gems and the philosopher's stone, both philosophical and practical. It was thought that the colors of metallic based glass pigments were an indication that the metals were "opened" and became susceptible to alchemical transmutation. Of special interest was the deep red ruby color made by adding gold to the glass melt. In the introduction to a 1797 French translation of Neri's book, artificial ruby or "vitrified gold," is equated to the bible's Electrum of Ezekiel —a red glow seen by the prophet in a vision.

By the mid-eighteenth century, Isaac Hollandus was lauded in industrial arts books as a genius of artificial gems. He may well have been, but the evidence does not support it. All of the specific recipes attributed to Hollandus seem to lead back to Neri's L'Arte Vetraria or its translations. A case can be made that Hollandus' reputation for artificial gems stems from a 1697 plagiarized version of Neri's book. A volume published in France by Haudicquer Blancourt that gives no credit to the Italian priest. Blancourt used Christopher Merrett's English edition of Neri as his base and added to the recipes with his own embellishments. The chapter on artificial gems still lauds Hollandus, but its length was now doubled from Neri's original set of seventeen recipes to thirty-five. Each the same basic formulation with different pigments added to simulate different gems. The size of this one section jumped from thirteen to nearly two hundred pages, an increase in page-count larger than Neri's entire book. He was adding pages, but not much new content. The expansion was accomplished largely by inserting the full base glass recipe into each color, and then expand the color range. In 1699, Blancourt's version was then translated back into English, again without reference to Neri. There is no doubt that these two editions, with their expanded chapters on paste gems exerted a strong influence on later craftsmen. They may also be the source of the credit given to Hollandus' for paste gems in the eighteenth and nineteenth centuries.

A number of intriguing questions remain unanswered. Chief among them is the nature of Neri’s association with the Dutch alchemist(s). Was Hollandus or his son (or brother, or cousin) alive in the first decade of the seventeenth century and did Neri meet with either of them in person? We can only guess. The Hollandus men are notable, if not enigmatic, characters in the transition from alchemy to modern chemistry. Historians would very much like to know them better. Nevertheless, there can be no doubt of the strong impact Hollandus made on Neri. Isaac holds a singular honor as the one person named in Neri's book to whom he gives specific credit. As research on early modern science has progressed, the importance of communication between practitioners has emerged as a central theme. A meeting of the minds between Neri and Hollandus, if it ever occurred, would rank as a prime example of technology transfer with a definite impact.

For a comprehensive look at Hollandus see: Annelies van Gijsen, "Isaac Hollandus Revisited" in Chymia: science and nature in Medieval and early modern Europe, Miguel Lòpez-Pèrez, Dider Kahn; Mar Rey Bueno, eds., (Newcastle upon Tyne, UK: Cambridge Scholars, 2010), pp. 310–324.
*This post first appeared here 2 April 2014.

Glassmaker 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 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 Spanish 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.

Neri in Antwerp

 

"The Blue Tower" Jozef Linning 1868.

There are three known facilities where priest Antonio Neri worked as an alchemist formulating glass in the early seventeenth century; in Florence, Pisa and Antwerp. If he did work elsewhere, it must have been for a relatively short period since his time at these three locations accounts well for his entire career. Of the three, he is known best for his work at the Casino di San Marco, on the north side of Florence. It is also the facility about which the most is known, since its owner was Medici prince, Don Antonio. However, a good argument can be made that the facility in Antwerp, about which much less is known, was the one most influential to his career as a glassmaker.

Neri traveled to Antwerp in early 1604 to visit his friend Emmanuel Ximenes (Pronounced Se-men-ez), where he stayed for seven years. Ximenes was an international trader (known then as a 'banker') from one of the wealthiest families in Flanders. At the time, Antwerp stood at the center of the bloody Dutch war for independence from Habsburg Spain. The population of the city was a shadow of its former self, after being sacked and burned by Spanish troops a couple of decades earlier in what has become known as "the Spanish Fury." A Dutch blockade of Antwerp's seaports had strangled commerce, but for the ultra-wealthy, life went on.  

"Antwerpen, het Arsenaal" Jan Wildens, 17th Cent.

 In his book on glassmaking, L'Arte Vetraria, [1] Neri names "the most courteous gentleman Filippo Gridolfi" as the owner of the glass factory in Antwerp. Indeed, records show that Gridolfi was the latest in a long line of who had been granted exclusive rights to make the exalted Venetian style glass known as cristallo. Previously, the facility had been run by Sara Vincx, with Gridolfi her foreman. This is the earliest documented case known to me of a glass furnace run by a woman. After their marriage, the luxury glass business thrived in Antwerp. In the 1590s, they employed seventeen Venetian workers. And later still they hosted Neri, who stayed in the area for seven years.

The most fashionable street in Antwerp was the Meir. This was the address of  Ximene's palace, as well as of his brother in law, Baron Simon Rodrigues d'Evora, who happened to be the most prestigious diamond dealer and jeweler in the region; he was known locally as "the little king." Gridolfi and Vincx had one, and later a second retail space for their glassware here. The factory and furnaces were located a few blocks away, near the fortress wall that ringed the city. Records indicate it was in a district called  the Hopland, near -- or possibly also in -- a huge structure actually built into the defensive wall around Antwerp. Called the "Blauwe Toren" [Blue Tower] for its blue slate roof, this impressive building had at various times functioned as an armory and a storage facility. In this period, a below street level canal led from the basement of the tower directly to the Meir, in later years the canal was filled in. Just on the other side of the city wall was a mote with access to the network of waterways which connected towns and villages throughout the region; this too was eventually turned into usable real estate when the wall was demolished in the nineteenth century. This situation of the glass production facility makes perfect sense. They needed to bring in heavy materials, ship delicate product and occupy a space which was not in danger of burning down the city should disaster strike. 

Blue Tower, 1860. Edmond Fierlants.

Today the foundations of the Blue Tower are preserved just below street level in a busy traffic square. Over the centuries, surrounding structures came and went. A small number of contemporary depictions do exist. Two illustrations that give a flavor of the neighborhood are shown here. One sketch by Jan Wildens  is not in the best of condition, but shows the tower and a few nearby structures from canal level in the seventeenth century. This might well have been typical of the view from a barge making deliveries. The factory would need a steady supply of pure quartz river stones used to make the exceptionally clear cristallo glass. A second view by Jozef Linnig, shows the neighborhood more clearly albeit in 1868. By then a furniture maker was located to the left of the tower, and another structure stood where the canal once was. Also of interest is an early photograph of the tower before it was demolished.

What we know of Neri's experiences in glassmaking come mostly from his book. His activities in Florence included making aquamarine colored glass for beadmaking and chalcedony glass with its multicolored swirls. In Pisa, he made emerald green, pimpernel green and celestial blue glass, he experimented with enamels, constructed a frit kiln and made glass using fern plants. From his early glassmaking activity in Florence, Neri seems to build momentum in Pisa. In these two locations combined he spends at most four years, in Antwerp he spend seven years, and there is no indication that he was slowing down, in fact quite the opposite. There he made artificial gems, a "beautiful aquamarine so nice and marvelous, that you will be astonished." He tinted rock crystal "the colors of balas, ruby, topaz, opal and girasol." He "built a furnace that held twenty glass-pots of various colors" He made ultramarine, the deep blue pigment valued by painters more highly than gold. Finally in 1609, in Antwerp, at Gridolfi's shop he made "the most beautiful chalcedony that I have ever made in my life" and presented two vessels of this glass to the prince of Orange.

[1] Neri 1612.
* This post first appeared here on 1 October 2014.

Colors of a Glassmaker

 

The European Roller [Pica Marina]

Antonio Neri's book, L'Arte Vetraria, is devoted to making glass from raw ingredients found in nature. Many of his finished creations were intended to also resemble the natural world. A number of colors are meant to mimic the appearance of gems and minerals, others are named after plants and animals. Some are easily recognized today, even if they are not as familiar as they were in the seventeenth century. One of his recipes will make "a wonderful pimpernel green," while others evoke peach and orange blossoms. An entire section of the book is focused on paints that are named after the flowers from which the colors are extracted. Many of these plants have remained common: poppies, irises, violets, lilies, carnations and red roses. Others are less so: the mallow, pomegranate, broom and borage flowers.

In addition to flora, the fauna make a few notable appearances in Neri's book. In chapter 16, in the preparation of iron oxide pigments, he advises that after fifteen days in the furnace, the product will be finished when it takes on the purple color of the peacock. In chapter 73 he gives a method for "tinting rock crystal the color of a viper" and chapter 121 is the method for a glass which is "red like blood."

Named in several chapters is a shade of 'celestial blue,' which Neri likens to the color of the "gazzera marina." Common bird names pose a special challenge for translation in that they, like the birds themselves, never seem to settle in space or time for very long. Vernacular names of a species can change from one century to the next, one region to another, even between adjacent valleys and several species can share the same name. It is with this admonition that we attempt to flush out the elusive gazzera marina.

Consulting a modern Italian dictionary draws the eye to the similar sounding 'gazza marina' (alca torda), known in English as the razorbill. This sea bird inhabits coastal cliffs, but alas, as a close relative of the penguin, it dons only black and white formal attire. Digging deeper we find poet Gabriele d'Annunzio, "At Dawn" carefully tracking the gazzera marina across a salty marsh, in his Halcyon. This time the poet himself throws us off the trail with his description, since no bird sports five digits but the chicken. Turning to etymology, we find another potential match in the magpie (pica pica); it is a credible but unconvincing fit with its blue and white plumage.

Aldrovandi's pica marina

Combing the references of Neri's own sixteenth century, we find the best candidate is the roller (pica marina). This bird was described by naturalist Ulisse Aldrovandi, a friend of Don Antonio de' Medici's father and guest at the Casino di San Marco, where Neri later worked. Other contemporary authors list the gazzera marina as a synonym to Aldrovandi's pica marina. Neri's Latin translator Frisius (1668) and his German translator Geissler (1678) agreed, both sighting the "Pica Marina" in their works.

This post first appeared here on 13 Sept 2013.