Conciatore: The Life and Times of 17th-century glassmaker Antonio Neri  chronicles Antonio Neri’s life as an apparent jack-of-all-trades in Baroque Florence. Neri worked as an alchemist, priest, and physician, but he struck gold with his seminal work, L’Arte Vetraria (The Art of Glass). In this treatise, he outlines his practical and philosophical approach to glassmaking, which–like many burgeoning sciences at the time–drew on traditions of magia naturalis (natural magic). It contains many references to the Neapolitan natural philosopher Giambattista della Porta, one of the illustrious “professors of secrets” of the Early Modern world. Conciatore has been well-received by peers. Science blogger The Renaissance Mathematicus has called it “first-class”. We spoke with the author of Conciatore, Paul Engle, to learn more about Neri’s intriguing life.

An alchemist in his laboratory by James Nasmyth.

An alchemist in his laboratory by James Nasmyth.

The Custodian: The Early Modern era saw the rise of countless geniuses, such as Isaac Newton, Galileo Galilei, and Athanasius Kircher. Why were you drawn to Antonio Neri in particular?

Paul Engle: I fell backward into learning about Neri; my wife, Lori, is a glass artist and in the late 1990s we had the opportunity to acquire an early Italian edition of his book of technical recipes, L’Arte Vetraria. A Venetian friend heard that I was translating the book into English, purely for my own amusement. Emilio made the case and eventually persuaded me to publish.

A curious thing happened along the way; in my research, I started to find new material on a regular basis. I discovered two long forgotten manuscripts written by Neri at the University of Glasgow and the more I dug, the more I found. I became fascinated with the life of the man who wrote the famous first printed book on glassmaking. He was a Catholic priest whose training in alchemy was apparently supported by his religious order.

His strong network of connections emphasises how collaborative his craft was, the opposite of the stereotype alchemist toiling alone in a dark basement.

I also discovered more about his family – he was the son of an acclaimed physician, in fact the personal physician to the grand duke of Tuscany. His grandfathers were a barber surgeon on one side of his family, and a lawyer to Michelangelo on the other. These discoveries lead to my current book, a biography titled Conciatore, which was the name in Florence for the professional who formulated the glass melt from raw materials.

The Neri family crest

The Neri family crest.

C: Can you tell us a bit more about the culture of Florentine glassmaking? 

P: There is a five-thousand-year-long history of glassmaking and the region around Florence contributed to that since early times when it was part of the Etruscan empire. Much later, in the mid-sixteenth century, shortly before Neri was born, there was utilitarian glasswork, church window painting and spectacle making. However, the very best glass and talent were to be found to the northeast on the tiny island of Murano in the Venetian lagoon. They supplied glassware to royal families throughout Europe and their reputation for excellence extended to the far reaches of the known world.

Around 1570, the grand duke of Tuscany made a deal with the Doge of Venice to bring a master glassmaker and two assistants to Florence from Murano. These men taught their techniques and set up a furnace at the Uffizi palace, which today houses the Florentine art museum. They built another furnace at the Casino di San Marco, which was a laboratory run by the duke’s son Francesco. A couple of decades later, Neri worked at that laboratory facility and at a third furnace that was set up at Pisa, also staffed by Venetians.

Florence is sometimes called the seat of the Renaissance, partly because of the great creative talent that flourished there. The Medici grand dukes spent enormous sums promoting the arts and in return, they used the fruits of those arts to leverage the city’s reputation. Lavish artisanal gifts paved the way for alliances and intermarriages with the ruling families of the much larger states in Europe. Neri played a part in that tradition, working both as an alchemist and a glassmaker for Prince Don Antonio de’ Medici. Medicinal kits made at the Casino became a coveted takeaway gift for visiting diplomats and royalty.

The Alchemist by Francois Marius Granet.

The Alchemist by Francois Marius Granet.

C: How was Neri’s book, L’Arte Vetraria received by his peers? 

P: The answer partly depends on whom you consider his peers: employees of the royal court, clerics in the church, other alchemists, or fellow glassmakers. There is no doubt that it was a feather in the Medici’s cap to publish an authoritative book of glass technical recipes. Bringing prestige to the church would also have been applauded. As an alchemist, one of Neri’s theoretical works was plagiarised – word for word – by a student of Athanasius Kircher, so he must have carried weight in that realm. Among glassmakers, we can guess that there was some resentment for spilling the secrets of another man’s trade. However, the book went on to become the bible of the art for the next two centuries.

One early exchange that is recorded is between Galileo and Roman prince Federico Cesi, the founder of one of Europe’s first scientific societies, the Lincei. In a letter dated two years after Neri’s death, Cesi pleads with Galileo to obtain and send a copy of Neri’s book, complaining bitterly about Roman librarians’ inability to secure worthy volumes. Galileo sent Cesi one and kept another on his own bookshelf. Cesi wrote back that he was thrilled with Neri’s work, thanking his friend the astronomer.

C: In addition to working as a glassmaker, Neri also served as a priest. Did he believe glass had certain spiritual or liturgical qualities?

P: This is a difficult question to answer because it is so easy to have our vision of that time clouded by our modern conceptions of religion. First, it is important to understand that Neri considered himself foremost an alchemist. For him, glass formulation was more of a practical application that he found himself doing and he was very good at it. As soon as the book was published, however, he turned his attention away from glass to medicine and chemistry, which he considered “higher callings”. In that realm, he was convinced that even with the correct materials and formulas, successful transmutation required divine assent—that the procedure would not work without a nod from above.

A second important point is that alchemists of this period considered glass to be a tool to unlocking nature’s secrets. When metal oxides were added to clear glass they produced bright colors; Blue and red from copper, green from iron, white from tin, violet from manganese, rich blue from cobalt. These colors were thought to be evidence of the deeper essence of the materials and in a sense that is correct. Today we recognise the colors as a product of the atomic properties of the materials.

The investigation of nature was as much a part of Neri’s life as was religion. For him, these things were not compartmentalised, as they might be for us. It is fun to note in the glass book,  he recites the Apostle’s Creed to time a procedure in one recipe, and uses repetitions of the Lord’s Prayer for another. The science vs. religion dichotomy is largely the result of developments that occurred after his lifetime.

C: You’ve said that Neri “has often been considered a mysterious figure, steeped in the intrigues of alchemy and transmutation”. Would you say that Neri fits the description of a Renaissance “natural magician”?

P: Sure, in Agrippa’s sense that he was a practising adept. The mystery and intrigue, however, was largely a result of twists and turns in history, that occurred after Neri’s death. As the Medici dynasty wound down and the story of Renaissance and Early Modern Florence was written, Galileo was made a sort of patron saint of rational science. There was a concerted effort to downplay or even bury aspects of natural philosophy that did not fit with the new order of thinking. Alchemy fell into that category, considered by many to be an embarrassment. Neri’s work on the transmutation of base metals into gold and silver was roundly criticised as folly, by historians, by scientists and by figures within the Church. While his book on glassmaking continued to be cited as a shining example of solid, competent chemistry, the rest of his work and details of his life faded into obscurity.

There are contemporary reports that recount demonstrations performed by Neri that supposedly produced alchemical gold. One was even witnessed by a precious metals refiner, who was amazed. Alchemical demonstrations in those days were attended by strong expectations and an almost theatrical atmosphere. In many respects they more resembled modern magic acts than objective scientific experiments, so in that sense also, yes, he could be considered a “natural magician”. It is important to note, though, that of the lesser transmutation recipes that he did commit to paper, all of them involve chemical reactions or physical processes that were not understood at the time. Today, it is easy to see how they could be mistaken for real transmutations; all evidence suggests that Neri was completely sincere.

The story goes that word got around about his demonstrations and our priest was attacked one night by thugs demanding the recipe to make gold. He gave them a bogus prescription and the next day he packed his bags and left Florence for about eight years. There is no particular reason to doubt the harassment story and the part about leaving town is certainly true. The fact that he spent time in Pisa and then in Antwerp is well documented. When he eventually returned to Florence, he published the glass book, but only lived for a couple of years after that. He is reported to have promised his patron, Prince Don Antonio de’ Medici the secret of transmutation, but the prince was delayed in arriving at the priest’s bedside and the secret went to the grave with Neri. The prince then mounted an investigation to discover if the information had been left with any family, friends or associates. He went so far as to engage a medium in Venice to make contact with Neri in the afterlife, alas, to no avail. It is interesting to note that fifty years later, when one of Don Antonio’s sons died, among his effects was found a box of elixirs together with a short tract on alchemy, all by Neri.

C: Did Neri write any non-glassmaking treatises or texts?

P: Yes, in fact, of the dozen or so manuscripts and pamphlets authored by Neri, all of them except the glass book are about other subjects. For some of these we only have the titles, but in general, they focus on practical chemistry, medicinal cures and on Neri’s philosophy. The earliest manuscript was an ambitious work written between 1598 and 1600, and dedicated to “all of alchemy”. This one is populated by numerous ink and watercolor illustrations drawn by Neri himself. It was written just as he finished seminary. Among the scenes depicted are his coworkers, both male and female, working with chemical apparatus.

The Alchemist Sendivogius by Jan Mateyko.

C: Was he a member or patron of any guilds, laboratories, or learned societies, such as the Academia dei Lincei (Academy of the Lynxes)?

P: To my knowledge, no evidence has emerged that Neri was a member of any of the chartered academies that were popular at the time such as the Lincei. He was a part of Don Antonio’s group of investigators around the dawn of the seventeenth century and that could easily be considered as the functional equivalent of such groups.

Neri’s family was well connected though and the godparents of his brothers and sisters were among the members of academies, the Florentine senate, and even the papal curia.

In reference to the Lincei, there is a tantalising quote in a letter from Neri’s wealthy banker friend Emmanuel Ximenes, in which Neri is said to have the “eyes of a lynx”, but there is no evidence that this is anything other than a colloquial expression.

C: Are you working on another book on Neri?

P: At the moment, I have nothing further planned except to reissue the translation of his glass recipes in a single volume. But I have not closed the door on the potential of future work. I continue to make posts to the blog and I have made dear friends in the historical community through Neri, so I will always be thinking about him to some extent. I feel privileged to have learned so much about the late Renaissance era through the eyes of such an extraordinary individual. My research has been ongoing for over a decade, but the truth is there is much more to be done on the subject. I have connected many loose ends about Neri’s life, but in the process I have uncovered many more.

Biblioteca Medicea Laurenziana by Francesco Bartolozzi.

Biblioteca Medicea Laurenziana by Francesco Bartolozzi.

Paul actively blogs on Neri and related Renaissance curiosa. You can also follow him on Twitter.

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