On The Path of Antonio Neri

Antonio Neri, self Portrait,
from Treasure of the World. 1598-1600
(detail, enlarged and rotated).

After a month-long hiatus, I am back at the keyboard and ready to resume telling the story of Early Modern alchemist Antonio Neri a few paragraphs at a time. To my regular readers, thank you for your patience. To those who are new, I hope you will find material here that makes you want to come back for more. 

"Conciatore" is the name used in seventeenth century Florence to describe the specialist who prepared batches of glass from raw materials. Catholic priest Antonio Neri was one of these, and he is best remembered for writing the first printed book on the subject of glass formulation, in 1612, called L'Arte Vetraria [1]. This recipe book contains over a hundred different preparations that range from the commonplace to the spectacular. 

The book would go on to become the bible of glassmakers throughout Europe and what Neri became famous for, but the man himself became something of a mystery. Less than fifty years after his death, his first translator, British Royal Society fellow Christopher Merrett wrote in 1662 "Concerning our author, and this work, I find no other mention of him." This would become the standard line on Neri for next three centuries; an enigmatic figure, fabled to have been chased out of Florence by thugs seeking to learn the secret of the philosophers stone, which purportedly could transmute base metals into gold.

Passages on Neri written by eighteenth century historians Giovanni Targioni-Tozzetti and Francesco Inghirami went unnoticed or ignored and recognition was complicated by the move to distance 'real science' from alchemy. In the early 1960's Venetian glass historian Luigi Zecchin, working with Florentine scholar Enzo Settesoldi, located a birth record which seems to be a match for the glassmaker [2]. They also found the marriage record of his parents, Neri and Dianora, birth records for some of his brothers and a cache of letters to Neri from a rich banker friend, Emmanuel Ximenes. Research was interrupted in 1966 by the disastrous flood that devastated Florence. When the city dried out, the hunt for Neri's trail was resumed, notably by Paolo Galluzzi in a 1982 book on Paracelsianism [3] and in the 1983 thesis and related research by Maria Grazzini, a student of science historian Paolo Rossi.

It was becoming clear that Neri possessed other intriguing dimensions besides that of a glassmaker. He was a dedicated Paracelsian experimentalist who worked in his father's field of medicine as well as in a much broader context of chemical investigation. What makes much of his work so very interesting is that unlike many of his contemporaries, Neri sometimes took pains to write in clear, uncoded language that exposed rather than concealed the alchemist's methods. In this way he serves as a sort of bridge to some of the more obscure alchemical tracts, like the notebooks of his disciple Agnolo della Casa. 

In 2002, I identified two previously overlooked manuscripts by Neri. One is a copy of work done shortly before his death, sighting Pisa as his location. The other, Tesoro del Mondo, [Treasure of the World] is a lavishly illustrated work dedicated to “all of alchemy.” It contains dozens of color illustrations drawn by the priest's own hand. It was started in 1598, when he was just finishing as a student at seminary. Both tracts were mentioned briefly by George Farrer Rodwell in the 1870s, when they were apparently first brought to Scotland and ultimately became part of the Ferguson collection at the University of Glasgow. The Treasure of the World is a bound, handwritten volume currently on public display in Düsseldorf at the Museum Kunstpalast (through 10 August 2014); The Art and Alchemy exhibit there is well worth the trip to this lovely city [4]. 

In 2007 I finished publishing a three part translation of the glass book [5] and in 2011, Pieter Boer and I coauthored a bibliographic survey of all that was known to have been written by, to or about Neri during his lifetime [6]. The astonishing finding was that in fourteen documents by Neri, twenty-seven letters addressed to him and thousands of pages recording his experiments by fellow alchemist Agnolo della Casa, the only references to glass are in his famous book and several paragraphs in the letters. All the other material deals with the subjects most important to Neri himself; chemistry and medicine. 

Last year, Maria Grazzini published a translation of Neri's Discorso Sopra la Chimica [7], in which Neri explains his chemical philosophy, and offers a number of recipes for transmutation in plain language. In the course of her research, Grazzini discovered that the manuscript had been plagiarized in its entirety by the Jesuit polymath Francesco Lana-Terzi as a chapter of his 1670 book Prordromo [8]. Lana-Terzi has become known as the father of aeronautics, for his airship designs.

On this, the four hundredth anniversary of Neri death, the future looks brighter than ever for further study. Later this year Laboratories of Art, ed. Sven Dupré [9], will explore alchemy in the service of Early Modern crafts. It will include a chapter by Marco Beretta about the facility where Neri worked in Florence [10] and another by Fanny Kieffer on the laboratories at the nearby Uffizi palace [11]. Christine Göttler, Sarah Joan Moran and Sven Dupré have a new website devoted to Emmanuel Ximenes, which promises to publish the letters from Ximenes to Neri in English translation [12]. Finally, my book, Conciatore, The Life and Times of 17th century Glassmaker Antonio Neri will also be published [13].

References:

[1] Antonio Neri, L’Arte vetraria, distinta in libri sette, del R. P. Antonio Neri fiorentino. Ne quali si scoprono, effetti maravigliosi, & insegnano segreti bellissimi, del vetro nel fuoco & altre cose curiose. All’Illvst.mo et eccell.mo Sig., Il Sig, Don Antonio Medici. Florence, Giunti 1612. http://books.google.com/books?id=XcnYJuJpMbEC&pg

[2] Luigi Zecchin, Vetro e vetrai di Murano: Studi sulla storia del vetro, vv. 3, Venice: Arsenale, 1987.

[3] Paolo Galluzzi, “Motivi Paracelsiana nella Toscana di Cosimo II e di Don Antonio dei Medici: Alchimia, medicina, ‘chimica’ e riforma del sapere,” in Scienze, credenze occulte, livelli di cultura, Istituto Nazionale di Studi sul Rinascimento, Florence: Leo S. Olschki, 1982, pp. 31–62. [Italian].

[4] Exhibit: Art And Alchemy, Museum Kunstpalast, Düsseldorf, Germany. (5 April – 10 August 2014) http://www.smkp.de/en/exhibitions/current/art-and-alchemy.html

Exhibit Catalog: Art and Alchemy, The Mystery of Transformation. Museum Kunstpalast, Hirmer, 2014 (English ed. –while they last.) www.hirmerpublishers.com

[5] Antonio Neri, L’Arte Vetraria, The Art of Glass, Paul Engle ed.( Hubbardston, Mass: Heiden & Engle, 2003–2007), vv. 3.

[6] Pieter Boer and Paul Engle, “Antonio Neri: An Annotated Bibliography of Primary References” in Journal of Glass Studies, v. 52 (2010), pp. 51-67.

[7] Maria Grazia Grazzini “Discorso sopra la Chimica: the Paracelsian Philosophy of Antonio Neri” in Nuncius, n. 27, 2012. pp. 411-467. http://www.museogalileo.it/assets/files/pdf_news/Nuncius_027_02_2012_doc_inedita.pdf

[8] Francesco Lana Terzi, Prodromo ouero saggio di alcune inuentioni nuoue premesso all'arte maestra. Brescia: per il Rizzardi, 1570. [Italian] http://books.google.com/books?id=RKMMo1El6VAC

[9] Laboratories of Art, Alchemy and Art Technology from Antiquity to the 18th Century, Series: Archimedes, Vol. 37, Springer, 2014
http://www.springer.com/philosophy/history+of+science/book/978-3-319-05064-5

[10] Marco Beretta “Material and Temporal Powers at the Casino di San Marco (1574–1621)” in Laboratories of Art, Archimedes Volume 37, 2014, Springer, pp 129-156.
http://link.springer.com/chapter/10.1007%2F978-3-319-05065-2_6

[11] Fanny Kieffer, “The Laboratories of Art and Alchemy at the Uffizi Gallery in Renaissance Florence: Some Material Aspects,” in Laboratories of Art, Archimedes Volume 37, 2014, Springer, pp 105-127. http://link.springer.com/chapter/10.1007%2F978-3-319-05065-2_5

[12] Website: The Possessions of the Portuguese Merchant-Banker
Emmanuel Ximenez (1564-1632) in Antwerp http://ximenez.unibe.ch/

[13] Paul Engle, Conciatore, The Life and Times of 17th Century Glassmaker Antonio Neri, Heiden & Engle, 2014. 

Mother Dianora

Agnolo di Cosimo 'Bronzino',
"Portrait of Florentine Noblewoman"
(subject unknown , circa. 1540).

Antonio Neri's mother, Dianora Parenti, was the oldest of six children: three girls and three boys. She was born in Florence, on 11 February 1552, with the given name of Dora listed in the city's baptistery register. In all probability by the age of eighteen she was quite accustomed to helping her mother with the other children; Caterina, the youngest, was born less than a year before Dianora's wedding.

Her father and grandfather were prominent lawyers; together they handled much of the personal business of famed artist Michelangelo. On the 20th day of August 1570, Francesco Parenti walked his eldest child down the aisle to be joined, in holy matrimony, to physician Neri Neri. Two years later, their first child Lessandra was born. 

Historians Luigi Zecchin and Enzo Settesoldi identified four of Antonio's brothers, two older and two younger. They were Jacopo (1573), Francesco (1575), a second Jacopo (1577) and Vincenzio (1579). In addition to these five boys, there were at least two more brothers born later, Emilio (1583) and Alessandro (1587). And there were at least three girls, the first-born child Lessandra (1572) and two younger sisters: Maria (1581) and Lucretia (1584). 

In all, there were ten births by Dianora recorded in Florence, occurring almost like clockwork on a fifteen-month schedule. As did many women of the period, she spent a significant portion of her adult life pregnant. In her case, it was a span of sixteen years, carrying one child after another with minimal interruption.

The birth of a child in Renaissance Florence was no small occasion. Patrician families went to considerable expense on decorations, on food and drink for guests and on gifts for the mother and godparents. "The woman who gave birth, like a bride at her wedding, occupied for a passing moment a position of unparalleled honor,"* more than that, while a wedding signaled the transition from daughter to wife, the birth celebration was a rare social recognition of a woman as an individual.

A genealogical record of the eighteenth century, held at the State Archives in Florence (ASF), confirms most of the Neri children's births. It also sets the date of death for their mother Dianora at 1594 when she would have been forty-two years old. This means Antonio lost his mother when he was eighteen and his youngest brother Alessandro was a mere seven.

* Margaret L. King, Women of the Renaissance (Chicago: University of Chicago Press, 1991), p. 4.

This post first appeared on 11 September 2013.

Galleria dei Lavori

Giovanni Stradano  (Jan van der Straet) 

Alchemy Studio, 1571

In 1560, Cosimo I, Duke of Tuscany, commissioned Georgio Vassari to begin construction on the Uffizi Palace in Florence. Two wings of the structure frame a long, narrow courtyard leading out to banks of the Arno River. Today it houses one of Europe's premier art museums, but its original design was as the central administration of the Medici government. The lower floor held offices of the regional magistrates, and the upper floor of the west wing (above the mint) held a variety of workshops highlighting Tuscan industry. Cosimo built a glass furnace there, which he staffed with Muranese masters of the art. He won their expertise through long, hard negotiations with the doge of Venice. 

A 1571 painting by Giovanni Stradano is entitled the Alchemy Studio. It shows Cosmo's son, Francesco I, in the Uffizi surrounded by laboratory equipment and workers. Under the watchful eyes of a senior alchemist, he stirs a chemical preparation over a stove with intense concentration. The prolific glassware in this scene drives home the close relationship between glassmaking and scientific investigation.

By 1588 Francesco's brother, Ferdinando I de' Medici, formally declared this space the Galleria dei Lavori or 'gallery of the works'. There is no direct evidence that Antonio Neri gained his education in alchemy at this facility, but it makes a very attractive candidate. Of note to this story is that the German alchemist Leonhard Thurneysser passed through Florence in 1590, when Neri was fourteen-years-old and by several accounts preformed a transmutation of an iron 'chiodo' [nail] with a special oil. After the demonstration for Grand Duke Ferdinando, the nail remained on display for some time in the Galleria. Neri mentions the nail in his Discorso and Thurneysser is discussed in a 1601 letter to the priest from his friend Emanuel Ximenes.

* UPDATE: 24 Feb 2014, recent scholarship has cast serious doubt that Thurneysser was ever in Florence. This makes a meeting with Neri unlikely. I hope to make this the subject of a future blog post – stay tuned.

This post first appeared on 16 August 2013.

Waxing Moon Reprise

In Chapter 5 of L'Arte Vetraria, Antonio Neri shows how to extract salt for glass from fern plants in an evocative recipe. Fern was and still is widely abundant in Tuscany. It presented a ready source material for glassmakers of the region. Neri directs that harvesting of the plants be done in the spring:

Cut this herb from the ground when it is green, between the end of the month of May and mid June. The moon should be waxing and close to its opposition with the sun, because at this point the plant is in its perfection and gives a lot of salt, more than it would at other times and of better nature, strength and whiteness.

At first, it is tempting to dismiss this lunar influence as the product of a fertile imagination, but let us take a closer look. Tidal forces of the moon do in fact subtly affect plants, fish and animals in ways that can be measured. A closer look at Neri’s advice reveals reasoning that is hard to dismiss as mere astrological superstition. When the moon is waxing, tides rise and so do water tables. According to folklore, this is when sap rises from the roots of plants into stems and leaves. Sap carries the dissolved mineral salts required for glass. Neri also stipulates that harvesting should take place during lunar opposition. When the moon is 'opposed' to the sun, it is on the opposite side of the earth from the sun. In opposition, the moon is near full and rises as the sun sets. Plants see more light at night, leading to increased photosynthesis and growth.

In contrast, violinmakers from Cremona valued high alpine spruce called moon wood. Trees were felled in the wintertime, when lunar tides were low. This minimized the amount of vibration deadening sap in the wood. In his Natural History, Pliny relates Cato’s advice on felling trees in accordance with the lunar cycle. In fact, centuries-old tradition specified lunar conditions for a host of needs from construction timbers to cheese boxes.

This post first appeared on 5 August 2013.

Weights and Measures

Ford Madox Brown,  The Manchester Murals: 
"The Proclamation Regarding Weights and Measures, 1556."

In his book L'Arte Vetraria, Antonio Neri's glass recipes depended on precise amounts specified in units as small as the 'grano,' [grain] named after the weight (mass) of a single grain of wheat or barley. In interpreting his formulas, the glassmaker must understand the quantities he used. For us, there are unfamiliar units like the 'fiasco' and the 'dita.' The dita or digit was simply the width of a finger. A fiasco or flask was the volume of a glass wine bottle, about two-and-a-quarter liters in Florence or two-thirds of a US gallon - about half of British imperial gallon. (As an aside, there are many fanciful stories of how the word 'fiasco' came to be synonymous with failure or disaster, perhaps the most believable is that the losers of competitions or bets were expected to buy the next round of drinks.)

In addition to unfamiliar units, there is the problem of standardization; a pound in Florence weighed different from a pound in other areas as close as Massa or Piedmont. Each Italian city maintained its own set of master weights and volumes to which merchants were expected to adhere. In reality, the differences were minor and may have been more attributable to politics than accuracy. Since antiquity, commodity merchants realized that if their own set of weights used in sales were ever so slightly below the norm, over time a savings would be realized, not large but significant. Towns could apply this principle as well; it paid to set standards slightly above or below neighboring towns from which one was buying or selling various goods. In truth, the differences were not great simply because successful commerce demanded that buyers and sellers could agree and strike a deal.

Even in different countries throughout Europe and the Mediterranean, we find close agreement in the various units of measure. Neri's first translator, Christopher Merrett, made an interesting substitution in his 1662 English version of L'Arte Vetraria. In chapter 132, Merrett writes "six pints of water" for Neri's "libre sei di acqua," changing pounds into pints. At first, it seems odd to be converting weight into volume, but this was perfectly valid. At that time in England, the pint was defined as exactly a pound (of wine or beer). Sailors were often each allotted a pint a day; the pint was also one-eighth of a cubic foot. (A cubic foot was equivalent to a gallon.) This system was very convenient for shipping companies who needed to calculate cargo volume and ballast in their trade ships as well as avoid mutiny by running out of beer at sea. Later, in 1824 King George IV increased the gallon from eight to ten pounds of water, invalidating Merrett's substitution.

Other conversions were more problematic. As absolute measurements varied from place to place, the size of a batch would be larger or smaller; not a big worry. However, ratios were of critical importance to a recipe. Just as in baking a cake, an entire batch of glass could be ruined by changing the ratio of materials. This sort of difficulty was especially prevalent with the size of an ounce; the troy and apothecaries system were based on a twelve-ounce pound while the avoirdupois system used a sixteen-ounce pound. When Merrett wrote his translation, England had officially been under the avoirdupois system since Henry VIII and in 1588, Elizabeth I complicated matters further by raising the weight of a pound by about twenty-one percent. Meanwhile, Florence and much of Europe continued to use the troy system.

English glassmakers who wished to use Neri's book as a working document would need to know which system to use. Merrett's direct translation added a hurdle that would confuse the unaware. In order to approximate Neri's intended composition under the prevailing avoirdupois system, Merrett's "ingenious" British readers would need to decrease by 1/5 quantities specified in pounds, and increase ounces by 1/15.

This post first appeared on 18 September 2013.

The Old Post Road

In the winter of 1603-1604, Antonio Neri left Italy to visit his friend Emmanuel Ximenes in Antwerp. There is no way to know the exact path he took, but based on the advice in Ximenes' letters and on well-established trade routes; a good estimation can be made. The path he suggested, if Neri was starting from Pisa, took the priest first back east to Florence, then perhaps through Bologna, Ferrara and Padua to Venice. Ximenes offered to make arrangements for Neri to travel from Venice with traders headed to the Frankfurt fair held at mid-lent. There would have been plenty of time for him to celebrate Advent in Florence and Christmas in Venice before his caravan headed north. The group could have left as late as the end of January.

Ximenes suggested that Neri travel with the courier from Florence to Venice. He was referring to the system of coaches that delivered the mail throughout Habsburg Europe, run since the early 1500s by the De Taxis family. While the Medici and other heads of state maintained their own fast couriers for diplomatic and military messaging, the De Taxis had a monopoly on almost every other piece of correspondence, a privilege for the family that was later extended to other parts of the world. They ran an efficient system well into the eighteenth century. An elaborate series of posts were set up at intervals, where tired horses were watered and swapped for fresh steeds and riders so that the journey could continue uninterrupted. Independent travelers could partake in the system for a fee based on equipment required and the weight of luggage. In Neri's time, accounts were settled at each post and travelers could elect to stay over in a town and pick up a later expedition. On well-established popular routes like between Florence and Rome, travelers could pay a flat rate that included lodging and meals. If Neri had traveled light and spoke some German, he might have completed the entire journey in as little as ten days; the time letters from Venice to Flanders took to arrive.

On Embarking from Venice, the party of traders would head west, back to Padua, on to Verona and then north along the ancient trade route through Bolzano to the Brenner Pass. The journey from Venice to Frankfurt was about 600 miles (950 km). Traveling an average of 30 miles per day, they would be on the road for three weeks. Depending on their itinerary, the journey could have varied by a week in either direction. The start of the fair was mid-lent, the date of the traditional feast held three weeks before Easter. In 1604 mid-lent Sunday fell on 28 March.

Brenner is the lowest pass across the central Alps, connecting Bolzano on one side to Innsbruck on the other and was passable year round. The distance of this, most difficult part of the journey, was about 75 miles (120 km), with a vertical climb of 4,495 ft (1,370 m), almost a full mile, but all below the tree line. Assuming a slow pace for pack animals, this segment could still be completed in less than a week, stopping in Bressanone, (Brixen), then at the alpine city of Vipiteno (Sterzing), where perhaps some extra time was taken to rest and view the nearby silver mines. Gries am Brenner was just over the pass on the Austrian side. With the majestic Wipp valley (Wipptal) at their backs, the remaining journey was down hill from there. From Innsbruck, the traders would head towards Augsburg, perhaps with an excursion through Munich, which was then the capital of Bavaria. The route from Augsburg through Wurzburg to Frankfurt was riddled with small towns accustomed to hosting traders since Roman times. After a few weeks on the road, the fair at Frankfurt would have come as a welcome diversion.

At the end of the fair, a week before Easter, Neri would start the final 250 miles (400 km) of his journey. First, he would travel over land with merchants or the Ximenes family servant to the walled city of Cologne on the Rhine River. Next, he would move by water toward the sea. The northern route, along the Rhine, avoided the military conflicts between the Dutch Republic and the Hapsburg Empire. The most dangerous were between Liege and Antwerp. From Rotterdam, the inland waterways led south to Antwerp. Priest Neri may well have arrived in time for Easter Vigil.

This post first appeared on 21 October 2013.

Neri in Pisa Reprise

Majolica vase by Niccolò Sisti, 

decorated in the grotesque style.

Antonio Neri's career in glassmaking took him from the city of his birth, Florence, to Pisa, Antwerp and possibly other places yet to be established, like Rome and Venice. Under the reign of Grand Duke Ferdinando de' Medici, a glass furnace at Pisa became an important source of diplomatic gifts in both glass and ceramics. Antonio Neri worked at this facility in the first years of the seventeenth century. Later, the same foundry would receive an order for exceptionally clear glass to be used by Galileo in his telescopes. It is unknown how that project worked out, but the furnace master Niccolò Sisti made a name for himself supplying glassware to the Vatican, the king of Spain, and many nobles throughout Italy and Europe. Here is What I wrote last 18 October about Neri's tenure in Pisa with Sisti: 

In the early seventeenth century, there were several glass furnaces in Pisa. One was run at the pleasure of Grand Duke Ferdinando by Niccolò Sisti. Raised in Norcia in Perugia, he likely learned his trade at an early age;  Sisti's father, Sisto de' Bonsisti, was said to be an expert in making paste gems. This would account for the son's apparent skill in the medium of glass in addition to his ceramics prowess for which he was previously employed at the Casino di San Marco in Florence. For Neri, working at Sisti's glass house in Pisa played an important role in his glassmaking education. Sisti would serve three Medici grand dukes, Francesco I, Ferdinando I and Cosimo II. When work came to a stop at the Casino di San Marco, after Francesco’s death, Sisti may have opened his own factory in Florence for a short time, but then moved to a new facility in Pisa.

 In 1592, Grand Duke Ferdinando set up a glass shop in the central part of Pisa, along the north bank of the Arno River. This furnace was staffed by Muranese workers and was located in the city center, along the river. Archaeologists have unearthed its remains in the courtyard of what is now 43-44 Lungarno. The operation was capitalized with a loan of five hundred scudi made by Ferdinando I to Sisti, with a special mandate: he was to introduce new forms of pottery to the region. In addition to glass, the furnace at Pisa would produce soft-paste porcelain and majolica ceramics. These were both forms that Sisti had helped to develop when he worked in Florence at the Casino; he was involved in Francesco’s quest to duplicate Chinese porcelain.

In 1602, Neri was to be found working alongside Sisti at the Pisan furnace. According to his own account, this is where he worked on special colors, and collected river stones for glass frit. Here he made kermes based paints, enamels and used ferns as an alternative plant salt for glass. In all likelihood, he would have had access to the nearby botanical gardens and the small adjacent laboratory located just a few blocks from the glass furnace. 

Early in 1604, the priest would make his trip north to Antwerp to visit his friend Emmanuel Ximenes. During Neri's seven year absence, Sisti's projects included cristallo table service for the Vatican, and special glass for the lenses of Galileo's telescopes. Upon Neri's return from Flanders, we again find him working in Pisa, this time on alchemy. In a copy of his last known manuscript, a heading reads, "Techniques copied from an old book here in Pisa."  The university at Pisa was an intellectual center and a repository of technical knowledge. There, Neri had access to a wide range of materials in the libraries. The furnaces and laboratories provided him with hands-on experience, but there can be little doubt that he was a voracious reader as well. On the same page of this manuscript appears the date 26 January 1614. This is the last known specific information on the priest's whereabouts, since he would be dead within the year, at the age of thirty-eight.