Thomas Edison's Lady Glassblowers

Fig. 1. 
Sealing the Glass Socket and
Carbon Filament into the Flask of an Incandescent Lamp.
"We will next turn to the glass-blowing department, where
hundreds of girls are employed in all the delicate and skillful 
manipulations involved in the glasswork of these lamps"
-Henry Morton, Scribner's Magazine, Vol. 6, 1889

On a cold Monday afternoon in December of 1888, Thomas Edison, his wife Mina and their children arrived in Akron, Ohio, on the 12:17 train. They had traveled from their estate ‘Glenmont’ in West Orange, New Jersey, to visit Mina’s parents for the holidays. That same evening, after dinner, Edison and his father-in-law, Lewis Miller, donned winter coats and walked to a nearby station of the Akron Electric Light Co. where they inspected one of Edison’s dynamo generators that had recently been installed. The dynamo was wired by dedicated copper lines to ‘Oak Place’, Miller’s residence. Upon returning to the house, the family assembled on the third floor, along with a newspaper reporter, where a “mammoth Christmas tree” stood. That year, the tree was adorned with ornaments, tinsel, and also a special addition: forty incandescent lamps that, with a flick of a switch, blazed to life.[1] There is every chance that each of those forty lamps was crafted by female hands at Edison’s Harrison, New Jersey, factory.

Early on, Edison decided on a female crew of flamework glass artisans to perform the delicate manipulations of assembling and finishing the incandescent lamp bulbs, (fig. 1). These specialists crafted the glass parts of the lamps in a complex series of steps. The ‘stem’ makers formed a glass seal around the electrical wires that held the delicate filament in place. The ‘tubulators’ put a small hole in the top of the bulb and attached the glass tubing used to pump the air out of the bulb. Mating the stem to the bulb in an air-tight seal without cracking or damaging either was an art unto itself. All the while, workers needed to adapt on-the-fly to continual changes in materials, procedures and tools as the bulbs evolved and improved. What is known, is that in the early days,  production took place at the laboratory in Menlo Park. As demand for the lamps started to explode, a “shed” for the glass work was built and then expanded. Because of the rural location of the laboratory, there was a continual problem of recruiting qualified workers. Around 1880, Edison turned to the employment of school-aged girls and boys to fill the labor shortage. Here he got a first hand look at what they were capable of. The use of women and girls for this glass work was a tradition that continued for nearly five decades, through the transition into General Electric Co., right up until the work was fully automated.

It was a year earlier, in the spring of 1879 that Edison first made the announcement that he was ready to begin producing electric lamps. Newspapers at the time gave great credit to a German glassblower working for Edison, for bringing the inventor’s research to fruition. This was Ludwig Boehm. He previously worked for Heinrich Geissler in Bonn, Germany, producing electrical discharge tubes and vacuum pumps.[2]  Boehm possessed the glassblowing skills to quickly whip out one test lamp after another, but he also knew how to make the coveted vacuum pumps invented by Geissler. These were the leading edge of vacuum pump technology, far faster and more efficient at evacuating the air out of the lamps than other methods of the time. Edison’s achievement would have been impossible without Geissler’s work and it was Ludwig Boehm, the glassblower, who was the conduit.

By 1882, a new ‘Lamp Works’ factory was ready in Harrison, near metropolitan Newark. It had more floor space than they could possibly ever use, or so they thought. By 1889, Henry Morton, the president of Stevens Institute of technology wrote, “Hundreds of girls are employed in all the delicate and skillful manipulations involved in the glasswork of these lamps.”[3]

Fig. 2.
Laboratory notebook entry
signed solely by Mina Edison.

Edison kept a series of laboratory notebooks documenting experiments and potential solutions to problems, and for the lamps there were many problems. The entries are often signed by Edison himself or his assistants. It is interesting to note that for a period, his wife Mina co-signed some of Edison’s entries and several pages appear in her name alone. This shows her active participation at some level in events of the laboratory.[4] Fig. 2 shows an example of a page signed by Mina Edison, Dated 23 March 1886 with three diagrams of lamps. The top diagram is accompanied by text reading “Make lamps of all kinds of glass and list conductivity.” The next diagram shows a bulb with a special electrode off to the side. The text reads “polished silver. Also one of polished hard rubber.” The third diagram shows a lamp with two filaments and appears to read “copper filament to take out curr[ent] 10-” While the intent of these experimental setups may be lost, what is clear is that she possessed a working understanding of how the lamps functioned and she was proficient at circuit diagrams. Whether she influenced the decision to use female glass workers is an open question.

To become one of Edison’s glass technicians meant steady work in a booming industry, it also meant a first-hand introduction to divisive labor problems common to factories at the end of the 19th century. In the summer of 1889, the general manager of the lamp works took a trip to Europe and, based on British glass blowing practices, he ordered his superintendent in Harrison to immediately cut pay and institute a list of new work rules. The superintendent procrastinated, knowing a disaster in the making when he saw one. Upon the manager’s return in October, the superintendent was fired and the new rules and wages were posted. “The workmen immediately commenced to walk out, and it is likely that the entire force of two hundred will strike” wrote one reporter.[5] Four weeks later, the papers announced that “The girls employed in Edison’s lamp works at Harrison, N J, will go on strike today because of a reduction in wages.”[6] Four years later, an unrelated incident at the lampworks made the papers. It illustrates that even with a good work record and no problems with management, simply getting in through the front door unscathed was not a given. “There was a small riot at the Edison Lamp Works in Harrison, this morning, between several hundred men who were waiting about the gates of the establishment for work. Some objected to the presence of a number of Polish Jews and a free fight ensued, which resulted in a number being badly bruised. The police dispersed the crowd.”[7]

Fig. 3.
Wanted ad for Edison’s Harrison Lampworks factory.
The Boston Globe (Boston Massachusetts)
22 June 1894, Fri., p. 9.

Through it all, the business continued to expand by leaps and bounds. A continual stream of “wanted” advertisements ran in papers as far away as Boston (Fig. 3.) In 1896, Harper’s Magazine reported that  Edison’s lamp factory at Harrison employed “several hundred girls and men” turning out over six-million lamps per year.[8] Even with long hours and partial automation, the line would require at least a couple-hundred glass workers for the delicate hand-work necessary in order to produce what amounted to a new lamp finished every two seconds on the clock.[9]

In the early 1900s the processes for making the lamps was further automated, with women still running much of the equipment. By 1903 a single worker could turn out 600 completed bulbs per day.[10]  By 1912 the Harrison plant employed a total of 4000 workers. In 1918 the women glass workers at the plant met to discuss forming their own union in order to institute an apprentice system to ensure the trade remained healthy.[11] Ultimately the entire lamp factory was closed in 1929 and the work was distributed to more modern and fully automated facilities around the country.[12]

Fig. 4.
Finishing work by women on tungsten lamps, c.1927.
(Shortly before the manufacture of lamp bulbs was fully automated)
Notice the striking similarities to fig. 1. above, from
the same facility, 40 years earlier.

The individual women and girls who worked for the electric lamp factory in Harrison can be traced to some extent through census records. A survey of the 1900 US census found over a hundred female respondents listing the Edison Lamp Works as their place of employment [13] The oldest was Elizabeth Stultz aged 45, the youngest Tillie Glinik just 13. There were a number of sisters there working glass side-by-side. Mary and Carrie Wright were 26 and 16 respectively, while Barbara, Christina and Annie Etzel were 19, 18 and 17.[14]

There is also evidence that the use of female glassworkers for Edison carried overseas to his British lamp making operation. As an 18-year-old, Florence Small who lived in a suburb north of London, worked making glass ‘stems’ for the Edison and Swan Electric Light Company (Royal Ediswan). In 1911, she worked at their Ponders End facility in her hometown of Enfield. She thought enough of the experience to include that detail in her will, fifty years later.[15]

Those forty lamps on the Miller’s Christmas tree in 1888, along with millions of other lamps were created by the skilled female flameworkers of the Edison and later General Electric lamp works in Harrison. It is quite a legacy that from the time of the introduction of electric lamps in 1879, all the way to the invention of television in 1927, the delicate glasswork of the electric lighting industry was firmly entrusted to the competent hands of women.

[1] “A Talk With Edison”, The Summit County Beacon (Akron, Ohio), 2 Jan 1889, Wed, Page 7

[2] “A Very Skillful Glass-Blower” Chicago Tribune (Chicago, Illinois), 4 January 1880, Sun, p. 10. In US Census records and laboratory notebooks Boehm spells his own name “Ludwig K Böhm”. In later life, he reinvented himself as a patent attorney in New York.

[3] Henry Jackson Morton, “Electricity in Lighting” Scribner’s Magazine 1889 vol. VI, pp. 19-23 [compiled, pp. 176-200], (Charles Scribner’s Sons: New York) p. 192.

[4] 03/18/1886 Edison, Thomas Alva -- Technical Notes and Drawings (Edison, Mina Miller (Mrs Thomas A.)) Incandescent lamp [N314] Notebook Series -- Fort Myers Notebooks: N-86-03-18 (1886) [N314003; TAEM 42:815] Courtesy of Thomas Edison National Historical Park.

[5] The Nebraska State Journal (Lincoln, Nebraska), 12 October 1889, Sat. p. 4.

[6] The Brooklyn Daily Eagle (Brooklyn, New York), 11 November 1889, Mon. p. 4.

[7] “Edison Lamp Works Riot.” Reading Times (Reading, Pennsylvania), 5 Dec. 1893, Tue. p. 4.

[8] R. R. (Richard Rodgers) Bowker “Electricity, a Great American Industry”, Harper’s Magazine, Oct 1896, vol. 32, p. 710.

[9] In 1892 Edison began to automate the process of forming the outer bulbs, ultimately farming the work out to Corning Glassworks.

[10] John W. Howell And Henry Schroeder, “History of the Incandescent Lamp” (The Maqua Company: Schenectady, New York ,1927), pp. 165-172.

[11] “Have Mass Meeting of Lamp Works Employes” (sic.), The Fort Wayne Sentinel (Fort Wayne, Indiana) 31 December 1918, p. 3.

[12] In 1932 the Harrison factory was re-purposed for the Radiophone Corporation of America. RCA, which produced electronic tubes until 1976. The site was ultimately leveled and is now home to a shopping mall.

[13] Combinations of search terms targeted females working at the Harrison, New Jersey Edison/General Electric Lamp Works. Women found working there, but not listing a specific profession could have worked non glass blowing jobs. Conversely, many who were glass workers at the plant left the census field for 'employment' blank, or were not asked by the census taker and therefore not found in the search.

[14] No candidates could be found in the 1880 US census, and the 1890 census was largely destroyed in a fire at the Commerce Dept. in 1921.

[15] Probate details for Florence Small provided by https://www.terrys.org.uk/charts/c/crack301.htm

Fig. 1: Sealing the Glass Socket and Carbon Filament into the Flask of an Incandescent Lamp. 1889

Fig. 2: Laboratory notebook entry signed solely by Mina Edison.

Fig. 3: Wanted ad for Edison’s Harrison Lampworks factory. The Boston Globe (Boston Massachusetts) 22 June 1894, Fri., p. 9.

Fig. 4: Finishing work on tungsten lamps, c.1927.

Sara Vincx, Glass Maker

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.

Witch's Brew of Glass

Glass pumpkin evocative of chalcedony glass

Courtesy of  Smithsonian Museum store.

In honor of Halloween, we will take a detailed look at chalcedony glass; this is one of, if not the most colorful types of glass ever made. In the seventeenth century, it was extremely dangerous for glassmakers and artists, containing a veritable “witch’s brew” of toxic materials. In his 1612 book, L’Arte Vetraria, glassmaker Antonio Neri presents three recipes of which he is clearly very proud. Each of the three is attended by a complex list of ingredients. He describes the end result this way:

It will be adorned with so many graceful and beautiful areas of undulations, and enhanced with the play of diverse, lively, flaming colors, that truly it will seem nature cannot attain so great a height or grand a prize. [1]

In the same passage, Neri explains the importance of purifying each ingredient and eliminating all contamination. In so doing, he provides a fascinating insight into the thinking of an alchemist. He writes:

There is no doubt that in this art, when the ingredients are well prepared, they permeate the glass with dazzling lively colors. Impurities will ordinarily impede the entry of the tinctures into the glass, and prevent their intimate unification. However, when you open the colors of the metals well, and separate them from their impurities and sediment, their beauty will always by far surpass those that are common and ordinarily made in the furnace. [2]

To Neri’s mind, the metals used as pigments must undergo a process of “opening.” Once this was done, each metal’s characteristic color or “tincture” was free to permeate the glass, provided it was free of impurities. Today we might say that by reducing each metal into an extremely fine powder, the individual atoms more easily disperse in the glass. Neri’s “opening” process usually involved dissolving a pure metal in an acid and then slowly evaporating the liquid, resulting in a fine powder. Most color arises because, once in the glass,  the metal atoms block some parts of the spectrum, but not others. The result is that each metal gives rise to its own hue and only because it is dispersed in the oxygen rich environment of the glass matrix. 

 The striking point here is how the alchemist’s model was a perfectly adequate description for the times, in the same way that the atomic model works for us. Unfortunately, there was less awareness of the negative health consequences in some of these preparations. The evaporation of powerful acids could (and can) certainly cause acute respiratory and tissue irritation. However there were far more insidious dangers lurking in Neri’s chalcedony recipes.

Ribbed vessel, chalcedony glass, 17th century, 

 Museo del Monastero di Santa Giulia, Brescia.

In his first prescription, he dissolves silver, mercury, cobalt, manganese, copper and iron. [3] Some of these have been prepared with sulfur which also ends up in the mix. He evaporates it to a powder and adds it to well seasoned, good quality clear glass along with pulverized chimney soot. He notes “When you stir [the molten glass] thoroughly it gives off a definite blue smoke.” Specifically hazardous in this recipe is the formation of mercury fumes, which are extremely toxic to breathe. 

He advises that in the furnace the glass appears “as red as fire,” but that “master craftsman always pinches off the glass for the job with nippers, and reheats it, in order to make waves, undulations and interplays of the most beautiful colors.” The reheating process is known to modern glassmakers as “striking,” a maneuver that brings out surprising color in some glass formulations. He suggests that this chalcedony can be used to form drinking glasses to more shapely cups, saltshakers, flower vases and similar vessels.

In his second and more sophisticated preparation Neri dissolves the materials in groups, in six separate flasks, only then combining them. He also adds new materials: lead, zinc, “blue painters enamel,” antimony and red varnish. The final recipe for chalcedony introduces new purification procedures and increases the number of separate flasks to nine. Additional ingredients include metal sulfides, ultramarine, tin, arsenic (read: death's calling card) and crimson paint. 

It is tempting to dismiss a few of these ingredients, like red varnish, or pulverized chimney soot; organic materials that would readily decompose in the heat of the furnace. However, Neri is known to have been a careful experimenter and these additions may well have had an effect on the melt, even if not in terms of color. Of the third recipe, which Neri developed in Antwerp, he wrote: 

Many Portuguese gentlemen in the practice of appraising jewels said that nature could do no better. This was the most beautiful chalcedony that I have ever made in my life. While it may be quite laborious and take a long time to produce, the result is fit for a king. I presented His Excellency, the Prince of Orange, with two vessels of this chalcedony, which delighted him greatly. [4]

[1] Neri 1612, p. 34.
[2] Ibid.
[3] Manganese and cobalt were unknown as distinct metals, but were used in their oxide forms, mined as minerals.
[4] Neri 1612, p. 48. The prince of orange was Philip William.
* This post first appeared here on 31 Oct 2014.

San Giusto alle Mura

Window of  Santa Maria del Fiore cathedral,

Florence, Italy.

In Florence, at the very end of the street on which Antonio Neri spent his youth, Borgo Pinti, was the residence and estate of the Archbishop. Beyond were the city walls and the enormous wooden doors of the Porta Pinti gate (115 foot, or 35 meters tall). Just on the other side of the gate, which in Neri’s time was normally closed and guarded, once stood the San Giusto alle Mura monastery, built in the thirteenth century. Despite the similar name, there is no connection between the Ingesuati monks of San Giusto and the modern order known as the Jesuits, which was not formed until 1534 and recognized by the Church in 1540.

The monks at San Giusto were famous for the stained glass windows they made; hence one of numerous theories that the street name 'Pinti' may be a contraction of 'dipinti 'or 'dipintori' (paintings or painters). Using their own glass furnaces, the Ingesuati monks provided windows for the Neri family's church Cestello and for Santa Maria del Fiore among other churches. They also ran an art school and were famous for making the color pigments used by painters, producing a coveted ultramarine blue. Their customers included the likes of Leonardo, Michelangelo, Botticelli, Del Sarto, Ghirlandaio and Filippo Lippi. 

Apparently, the Ingesuati's artistic devotion was not matched by their religious observance. In his Lives of the Artists, Giorgio Vasari recalls the less than complimentary sentiments of the monk's own in-house chaplain, a certain Servite monk named Fra Martino. He notes that the monks do not read Mass, and that they, "do nothing but say paternosters ['our Father...'], make glass windows, distill herbs for sweet waters, dig their gardens, and perform other works of similar kind, but do not study or cultivate letters."

Antonio Neri has a slightly more positive opinion about the value of stained glass windows. In the introduction to L'Arte Vetraria, he waxes poetic: 

Glass is also a great ornament to God's churches since, among other things, many beautiful windows are made, adorned with graceful paintings, in which the metallic colors are so intense and vivid that they seem like so many oriental gems. 

The windows that inspired these lines may well have been made by monks of San Giusto. As a child, Antonio Neri had seen the striking windows in Cestello and in the city cathedral. It would be nice to be able to connect him to the Ingesuati, but in 1529, long before his birth, their entire complex just outside the Pinti Gate was dismantled in defensive preparation for the siege of Florence. The Florentine military cleared away the structures near the outside of the city walls. The monks of San Giusto alle Mura moved to the much smaller Calza Convent on the oltrarno, on the opposite side of town near the Porta Romana gate. They did not rebuild the glassworks at the new location and it is doubtful that any of the glass workers would have still been alive by the time Antonio Neri came of age.

This post first appeared here in a slightly shorter form as "Glass Monks" on 30 September 2013.

We Were Trojans

Giovanni Domenico Tipeolo, 

Procession of the Trojan Horse in Troy. 1773

In January of 1600, Antonio Neri finished an ambitious manuscript called Treasure of the World, which was devoted to "all of alchemy." On the first page of text after the contents, above the first recipe, on the first line, written in Neri's own hand, are two solitary words, "fuimus troes"; a celebrated quote in Latin from Virgil’s epic poem, The Aeneid. The words translate to "We were Trojans" or more specifically "We Trojans are no more." They lament the fall of a city, sparked by the deception of the great wooden horse concealing enemy soldiers. These were words spoken in grief, in a charged, emotional scene, accepting defeat. We were once proud Trojans, but no more. While the intended significance in Neri’s manuscript may be lost, it is further affirmation of his academic grounding. What rings through the fog of history in these words, is the unmistakable passion behind them.

        Tis come, the inevitable hour,
        The supreme day of Darden power;
        Our history’s ended: Troy’s no more,
        And all her mighty glory o’er. 
            - Aneid 2,324.
            (William King, trans.)

The scene in the Aeneid takes place at night, under the stars. The hero Aeneas  sound asleep, wakes from his bed to the burning pillage of his city. After years under siege, the gates of Troy were breached – not by brute force, but by cunning deception. The streets are in flames, piled with the bodies of slaughtered innocents. Panthus, the priest from the temple of Apollo, with his grandson in tow, runs to Aeneus and exclaims that Troy and the Trojans are no more: "Fuimus Troes, fuit Ilium." He entrusts Aeneus with the sacred vessels and icons from the temple. Aeneus fights his way out to safety, carrying his own father on his back. He goes on to wander the Mediterranean. Later he enlists the help of the Etruscans (the ancient Florentines). Together, on the banks of the Tiber River, he fulfills his destiny by founding the city of Rome, or so the story tells.

In its broadest interpretation, those two words written by Virgil in the first century BCE, fuimus troes, have since been used to evoke the human drive to continue after a devastating blow. The loss of their widowed father in 1598 put the Neri children into a similar situation. The following year, Antonio's younger brother Emilio died at the age of sixteen on Christmas day. Two simple words scribbled at the top of a manuscript, yet they evoke the imagery of a man fighting his way out of a burning city, carrying the temple's sacred treasure. Behind all the recipes for glass and medicine and alchemy, there is a man of flesh and blood, one who felt life’s cruelties yet did persevere.

This post first appeared on 30 August 2013.

Galleria dei Lavori

Giovanni Stradano  (Jan van der Straet) 

Alchemy Studio, 1571
(Inside the Uffizi Galleria dei Lavori)

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. Grand Duke Cosimo de' Medici 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 a demonstration was performed for Ferdinando de' Medici in Rome that purported to turn half of an iron nail into gold; the work of German alchemist Leonhard Thurneysser. In the 1590s, when Neri was being schooled, several accounts describe that the nail (chiodo) 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.

After Neri's death in 1614, his Medici sponsor, don Antonio commenced a search for the glassmaker's secret of transmutation, which Neri had promised. In testimony given by a royal goldsmith, who had, in July of 1596, witnessed a demonstration in which "gold" was made by Neri, he pressed the glassmaker, who told him that the transmutation was a technique learned from a German, done with ordinary vitriol.  

It is interesting to note that when iron is soaked in a solution of "blue vitriol" now known as copper sulfate, an ion exchange reaction takes place, where the liquid deposits copper and takes up iron from the nail. It would be well into the 18th century before this chemistry was adequately understood. What the royal goldsmith would have seen is  a dull iron nail turn the color of yellow metal before their eyes. Perhaps the goldsmith was not given the opportunity to further test the sample. 

True Colors

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.