Syncroton recovers daguerreotype lost to tarnish

July 11th, 2018

The intense radiation and light of the particle accelerator has done it again. We’ve already seen synchrotron X-rays read a long-erased Galen text, map the molecular composition of cannon balls from the Mary Rose and virtually open a heavily corroded 17th century box to reveal the medallions within in jaw-dropping detail. Now we can add daguerreotypes tarnished beyond recognition to the synchrotron’s ever-expanding abilities to resuscitate the fatalities of time.

The daguerreotypes in question belong to the National Gallery of Canada (NGC) in Ottawa, Ontario. Taken in the 19th century, they were so corroded and marred that all that was visible of one of them was a ghostly outline while the other was a hacked up Kandinsky abstract with not even the ghost of the sitter remaining. Their terrible condition made them ideal subjects for a new study on the chemical changes that cause daguerreotype degradation.

Daguerreotypes were made by exposing silver plates to iodine vapour and waiting for minutes until the vapour had made the plate light-sensitive enough to capture the image. The photographer would then develop the picture by exposing the plate to mercury vapour. A solution of sodium thiosulfate cleaned the plate of excess iodine leaving a stable image on the plate.

Pinpointing the smallest trace of chemical residue is what synchrotron technology does best. Over the past three years, researchers from Western University in London, Canada, analyzed damaged daguerreotypes at the Canadian Light Source (CLS). Findings published last year and earlier this year revealed the chemical compositions of different manifestations of tarnish, but the most recent report takes a great leap forward to reveal the people underneath.

This preliminary research at the CLS led to today’s paper and the images [lead study author and Western University phD candidate Madalena] Kozachuk collected at the Cornell High Energy Synchrotron Source where she was able to analyze the daguerreotypes in their entirety.

Kozachuk used rapid-scanning micro-X-ray fluorescence imaging to analyze the plates, which are about 7.5 cm wide, and identified where mercury was distributed on the plates. With an X-ray beam as small as 10×10 microns (a human scalp hair averages 75 microns across) and at an energy most sensitive to mercury absorption, the scan of each daguerreotype took about eight hours.

“Mercury is the major element that contributes to the imagery captured in these photographs. Even though the surface is tarnished, those image particles remain intact. By looking at the mercury, we can retrieve the image in great detail,” said Tsun-Kong (T.K.) Sham, Western’s Canada Research Chair in Materials and Synchrotron Radiation. He also is a co-author of the research and Kozachuk’s supervisor.

This research will contribute to improving how daguerreotype images are recovered when cleaning is possible and will provide a way to seeing what’s below the tarnish if cleaning is not possible.

The identity of the two people whose images have been recovered is unknown. One is a woman, the other a man, and both daguerreotypes are early examples, perhaps dating as early as 1850. The plate of the woman was bought at a garage sale and that’s all the NGC knows about it. There’s no information at all about the fella.

The full study has been published in the journal Scientific Reports and can be read free of charge online.


Ancient tablet of Odyssey found in Olympia

July 10th, 2018

Archaeologists have discovered a clay tablet inscribed with verses from The Odyssey in Olympia, Greece. Found next to the Temple of Zeus with Roman-era artifacts, the slab is engraved with 13 verses from Odysseus’ speech to Eumaeus. Preliminary analysis suggests it dates to the Roman era, probably before the 3rd century.

Olympia, the venue of the ancient Olympic Games, was a religious center from long before Homer was a twinkle in his mamma’s eye. There is archaeological evidence of burned offerings made at the site in the 4th millennium B.C. The first known temple was constructed in the early 7th century B.C. and was dedicated to Hera. Her husband overtook her in the mid-5th century B.C. when the Sanctuary of Zeus was built on a grander scale than any of the previous religious structures. The monumental gold and ivory statue of Zeus sculpted by Phidias (who had a workshop at Olympia) was one of the Seven Wonders of the Ancient World.

Olympia remained a cultural and religious beacon in the classical world even after it became part of the Roman Empire. Olympic games were still held and the faithful still flocked to the sanctuaries. It suffered from earthquakes and barbarian invasions in the 3rd century, but it wasn’t until the 5th century when it really came tumbling down. Literally. Eastern Roman Emperor Theodosius II ordered the Temple of Zeus destroyed in 426 A.D. and a series of earthquakes in the 6th century finished the job.

The tablet was discovered during geoarchaeological survey of the site as part of the Multidimensional Space of Olympia program, a project which explores the relationships between the sanctuary and surrounding areas. During three years of fieldwork (2015-2017), a multidisciplinary team of researchers did an intensive grid survey of ancient Olympia, its immediate surroundings and the nearby villages of Epitalio and Salmone. They made several important discoveries in the process — Mycenaean chamber graves, Bronze Age terracing, the remains of an ancient polygonal wall and one very special clay tablet.

The tablet’s likely age places it at the end of Olympia’s long history of Panhellenic prominence. It’s of enormous significance because even at so late a date it is likely the oldest written extract of the Homeric epic known to survive. It is now undergoing conservation and detailed epigraphic study which will confirm or deny the preliminary dating and hopefully narrow it down further.


Victoria’s controversial chocolate gift for sale

July 9th, 2018

Quakers were prohibited from getting academic degrees, so some of the traditional routes to respectable careers — medicine, law — were blocked off. The courses of study weren’t in keeping with Quaker religious standards anyway (“pagan” philosophy, “lascivious” poetry), and as Quakers increasingly engaged in wider English society and “worldly” activities like banking, commerce and retail in the 18th and 19th century, integrating their religious and ethical precepts into their business practices.

Chocolate was considered an “innocent trade,” as it was believed to have medicinal purposes and didn’t lead people into evil. Selling chocolate brought enjoyment and good health through the gifts of God’s nature. There was no moral corruption in making a nice cup of cocoa as there was in manufacturing weapons. Quakers went into the chocolate business when it was purely a beverage, developing it into the bar and candy empire that it is today. By the early 20th century, the three top chocolate and confectionary companies in England were Quaker owned and operated.

J. S. Fry & Sons was a Quaker family business. Founded in 1759, Fry’s bears numerous historic distinctions. It was the first company to use industrial equipment the chocolate-making process, the first to mass-produce a chocolate bar and the inventor of the chocolate Easter egg.

Cadbury’s was founded by Quaker John Cadbury. John started selling coffee, tea and chocolate beverages in 1824 and built it into a successful company. It too was a family business, first John’s brother Benjamin joined him as a partner in 1848. They worked together 12 years. By the time Benjamin withdrew from the partnership in 1860, the company’s fortunes were in decline and John retired in 1861 after his wife’s death. John’s sons Richard and George took over and brought the business back from the brink to a whole new prosperity, expanding the product line from chocolate beverage to bars like the iconic Cadbury Dairy Milk which popularized milk chocolate.

Fry’s and Cadbury’s largest competitor, Rowntree’s, followed in the same Quaker footsteps. Founded by Henry Isaac Rowntree in 1862, the company was run according to Quaker principles of loving virtue. All the top three chocolatiers paid well and provided education, housing, recreational facilities and health care resources for their employees. Cadbury’s was the first company to establish the five-day work week.

So when in 1899 Queen Victoria turned to Cadbury’s, holders of the Royal Warrant as suppliers of chocolate products, to make a bar as a New Year’s present for the English troops fighting in the Boer War, the Queen’s command clashed at the most fundamental level with the pacifist principles of the “innocent trade.” The Cadbury brothers could not profit from war, but neither could they tell Queen Victoria to go suck a lemon.

To resolve their dilemma Richard and George Cadbury formed a temporary alliance with Joseph Fry and Joseph Rowntree: The three firms agreed to work together to fulfil the order. They would donate the chocolate free of charge and there would be no branding on either the chocolate or the tins.

Queen Victoria was not amused by all this. She wanted her soldiers and sailors to know that she was sending them the best British chocolate. In the face of the Royal ire, the firms took the sensible course of action. They caved in. Sort of. The tins remained unbranded but some of the chocolate and some of the interior wrapping sometimes did bear a company name.

The final product was a colorful tin painted red, gold and blue and embossed with a portrait of the Queen. It was inscribed “I wish you a Happy New Year Victoria R.I” and “South Africa 1900.”

One of those Queen Victoria South Africa tins has come up for auction. It’s in fine condition and still contains the original chocolate bar, foil wrapping and paper covering. Small differences between the tins produced by the three manufacturers identify this one as having been made by Cadbury’s.

The auction closes July 10th at noon EST, and online bidding is open. Only seven bids have been submitted so far, the top one is £84, enough to cover the reserve. The high estimate is just £120, so unless a bidding war breaks out (I think metaphoric wars are okay, Quaker-wise), this stale, faded, beige chocolate in a fabulous tin is something of a bargain.


Buon Compleanno, Artemisia!

July 8th, 2018

Baroque master Artemisia Gentileschi would have been 425 years old today. The first woman granted membership to Florence’s Accademia del Disegno, she was famous in her time and counted the crowned heads of Europe among her clientele. Her striking works, often featuring illustrious women from history and the Bible, have become icons of female representation during a time when women were largely excluded from the painterly ranks.

Her private life has been inextricably woven into her oeuvre. She used herself as a model frequently — a number of self-portraits of her as saints, artists and allegories, particularly from her Florentine period, have survived — and her powerful female protagonists have been adopted as symbols of empowerment in the wake of her rape and the subsequent trial of the perpetrator, her art teacher Agostino Tassi. We know from the incredible survival of the transcripts that she stood up for herself at the 1611 trial even under torture. (Rape accusers in the Papal States were subjected to the thumbscrews, among other torture techniques, to ensure their veracity.) For many years she was treated by art historians something of a curiosity, a successful woman artist with a tragic personal history that seemed to be reflected in works like Judith Slaying Holofernes.

The worm has turned for Artemisia, and the understanding of her art on its own terms rather than as mere Caravaggista works or as fodder for five-cent psychological interpretations has led to a massive uptake in interest and demand from museums and collectors. In 2014, a rediscovered Mary Magdalene in Ecstasy broke the sale record for an Artemisia Gentileschi painting when it sold for €865,500 (ca. $1,175,000). In December of 2017, another rediscovered work, Self Portrait as Saint Catherine of Alexandria (ca. 1615-1617), went up for auction in Paris. It broke the new record even more dramatically than the 2014 sale had broken the 1998 record, selling for €2,360,600 ($2,775,000).

Well, we can kiss that record goodbye too, because less than a year later, the dealer who acquired Self Portrait as Saint Catherine of Alexandria has sold it to London’s National Gallery for £3.6 million ($4,784,000). Paying this eye-watering price was made possible by donations from the American Friends of the National Gallery, the National Gallery Trust, Art Fund, Lord and Lady Sassoon, Lady Getty, Hannah Rothschild CBE, and others who prefer to remain anonymous.

It is the first work by a female artist bought by the National Gallery in almost 30 years, and is only the 21st painting by a woman to join the 2,300 works in the NG’s permanent collection. It’s also just the third easel painting by Artemisia Gentileschi in England.

Self Portrait as Saint Catherine of Alexandria depicts the saint turned toward the viewer. The figure is identifiable as the saint because of the spiked wheel on which she rests her left hand, the means by which Saint Catherine was supposed to be martyred in the 4th century by order of the Emperor Maxentius only for it to break the moment she touched it. He ordered her beheaded instead and that one did the trick. Unique for her time, Artemisia crops the scene very tightly around the upper body of the saint. This is something you see repeatedly in her portraits of herself as other people.

Letizia Treves, The James and Sarah Sassoon Curator of Later Italian, Spanish, and French 17th-century paintings at the National Gallery say:

“Artemisia is without question one of the most celebrated painters of her time, and we have long wished to acquire a painting by her for the national collection. The fact that this is a self-portrait adds enormously to the painting’s appeal and art historical significance. We are fortunate to have one of the strongest collections of Italian Baroque paintings but, with the exception of Caravaggio, no Italian artist of the 17th century surpasses Artemisia in terms of fame and popular appeal. Following conservation treatment and reframing Self Portrait as Saint Catherine of Alexandria will find a natural home alongside other works by Italian Baroque painters, including Caravaggio and Artemisia’s father Orazio Gentileschi.”


Roman inscription found in Thracian city

July 7th, 2018

An intact Latin inscription has been unearthed in an excavation of the ancient Thracian city of Kabyle near modern-day Kabile in southeastern Bulgaria. It is the first complete Roman inscription discovered in Kabyle in 35 years, a notable gap in a city that had a strong Roman presence from its conquest in 71 B.C. until the Gothic invasions of the 4th century.

The marble slab engraved with the inscription is two feet high by 2.6 feet wide. The seven lines of Latin inscribed on the slab refer to the construction of the public baths between 166 and 169 A.D., during the reign of Emperor Marcus Aurelius (161-180 A.D.).

The Kabyle thermae were built by the Cohors II Lucensium (Second Lucensian Cohort), Roman military unit based in the Thracian city at the time. The unit was commanded by prefect (praefectus) named Elius Rufus.

The stone slab itself has been found near the principia (plural of principium), the building for the command staff of the respective Roman military unit.

“All in all, the inscription’s translation reveals that the thermae in Kabyle were built by the Cohors II Lucensium (Second Lucensian Cohort) at the time when the Thracia province was governed by Governor Claudius Marcialus,” Bakardzhiev has told the BNT TV channel.

Before the discovery of the slab, archaeologists didn’t know anything about the Second Lucensian other than that it arrived in Kabyle in 136 A.D. The inscription confirmed not only that the Second Lucensian built the baths under the command of Elius Rufus, but that the site of excavation was in fact the cohort’s principia.

This is only the fourth inscription found in Kabyle that provides concrete information about Roman building projects in the city. The baths, one of the most extensive public structures built in Roman Kabyle, didn’t even have a clear date of construction until the discovery of the inscription.


Dolmen found during carpark construction

July 6th, 2018

Archaeologists have unearthed a 3,000-year-old dolmen during construction of an underground car park in Sion, southwestern Switzerland. The parking deck was being built at the late Bronze Age, early Iron Age necropolis of Don Bosco as the excavation of the last graves was coming to a close. The dolmen long predates the necropolis.

Sion is of the richest prehistoric sites in Europe with the earliest evidence of settlement going back to 6200 B.C. Early farmers arrived around 5800 B.C. but settlement really started taking off in the middle Neolithic, ca. 4500 B.C. That’s when burials in stone cists began. Those individual tombs gave way in the 3rd millennium B.C. to large communal tombs erected out of dry stone slabs with engraved stele, ie, dolmens. The stone vaults could contain more than a hundred individuals.

This dolmen was found in parts with only one slab in its original position. Located on the alluvial plains of the Sionne, a tributary of the Rhone, the dolmen’s slabs were likely shifted by river floods and currents. They smallest of them weigh several tons. Similar stone slabs have been found dotting the perimeter of the construction site, so it’s likely there was more than one dolmen there.

The find site will be excavated further in the hope of finding human bones still inside the associated burial chamber. It’s a slim hope given the river floods which were powerful enough to dislodge heavy stone slabs. Archaeologists will also look for dateable material to pinpoint the age of the dolmen and later findings from the Celtic necropolis.

The stones will be recovered, cleaned and conserved. Experts will examine them with a variety of imaging techniques, raking light, laser scanning, etc. to determine whether any of the slabs are engraved.


European police seize 25,000 trafficked artifacts

July 5th, 2018

” rel=”noopener” target=”_blank”>A coordinated sting of an antiquities trafficking operation executed in four European countries has resulted in the seizure of 25,000 ancient artifacts worth an estimated 40 million euros ($46 million). The pre-dawn action saw more than 250 law enforcement officers raid 40 different locations in Italy, Spain, Britain and Germany, and arrest 23 individuals.

This is the culmination of four years of investigation into a major smuggling ring that began with the discovery of a looted archaeological site in the small town of Riesi in the Caltanissetta area of central Sicily. Before the coordinated raids, Italian authorities confiscated 3,000 artifacts, 1,200 forgeries and 1,500 tools of the looting trade including metal detectors.

The stolen artifacts, mostly coins, statues and pottery, all seem to have been illegally excavated in and around Caltanissetta which has a rich Greek, Punic and Roman history. From there, the objects were smuggled up the boot of Italy, out of the country to Germany where they were sold with ginned up ownership histories. Police searched locations in Sicily, Calabria, Piedmont and Apulia, one the largest crackdowns on heritage crime in Italian history.

Europol, which financed the meetings between each country’s forces, said that key facilitators in the trafficking ring were “also acting from Barcelona and London, coordinating the supply chain and providing technical support”.

Metropolitan Police officers acting on a European arrest warrant issued by Italian magistrates Wednesday arrested the art dealer, Thomas William Veres, 64, in London, a Carabinieri paramilitary police spokesman told a news conference.[…]

The Sicilian smuggling operation is alleged to have been masterminded by Francesco Lucerna, 76, another of those arrested Wednesday.

Mr Lucerna regularly dispatched stolen archaeological remains to northern Italy through a network of couriers where they allegedly made contact with Mr Veres’ gang, investigators believe.

The gang also set up workshops where teams of counterfeiters copied some of the archaeological remains and sold replica copies as originals, it is alleged.

The investigation into the vast operation is still ongoing. The two auction houses in Munich which regularly received and sold the smuggled artifacts are under investigation as well.


Largest sarcophagus in Alexandria found

July 4th, 2018

A massive black granite sarcophagus unearthed in the Sidi Gaber district of east Alexandria is the largest ever found in the city. It dates to the Ptolemaic dynasty when the city founded by Alexander the Great in 332 B.C. was the cultural and political capital of Egypt. The sarcophagus is an extraordinary 8.7 feet long, six feet high and 5.4 feet wide.

It was discovered during an archaeological survey at a property on Al-Karmili Street in advance of construction of the foundations of a new building. The sarcophagus was found 16 feet below ground level. Next to it was a heavily eroded head carved out of alabaster.

The sarcophagus is fully intact and the lid and body are still sealed together with a layer of mortar. That leaves open the exciting prospect that the individual laid to rest within it still resides there, perhaps the same individual depicted in the alabaster sculpture.

The site is being secured by to keep it safe from looters. The coffin and head will be removed for study, but special arrangements must be made to raise the massive coffin. The Alexandria Antiquities authority is coordinating with armed forces engineers to recover the artifacts.


Rare 1745 portrait donated to Colonial Williamsburg

July 3rd, 2018

The descendants of Joyce Armistead Booth have donated an extremely rare surviving portrait of their ancestor painted by 18th century artist William Dering to the Colonial Williamsburg Foundation. Only six of Dering’s portraits are known to have survived — including one of Joyce’s son George — and with the latest donation the Colonial Willamsburg foundation is now the proud owner of five of the six.

Only one of the portraits attributed to William Dering is signed. Experts use it as the standard to determine attribution of other works that crop up. The painting of Joyce Armistead Booth has been in the family since it was painted. It is in excellent condition and is still in its original frame. This is an inestimable resource for art historical research into Dering’s oeuvre.

“Executed in saturated, well-preserved reds, blues, and golds, and measuring more than four feet in height, this likeness of Joyce Armistead Booth is visually arresting,” said Ronald L. Hurst, the foundation’s Carlisle H. Humelsine chief curator and vice president for collections, conservation and museums. “The portrait commands the viewer’s attention, and in so doing, provides a window into the goals and aspirations of early Virginia’s planter aristocracy.”

This Dering portrait is significant to ongoing research that Colonial Williamsburg’s experts are undertaking. Laura Barry, Juli Grainger curator of paintings, drawings and sculpture, and Shelley Svoboda, senior conservator of paintings, are at work on a comprehensive study of the artist and his work from both historical and technical perspectives. The portrait of Joyce Armistead Booth, especially due to its pristine condition, informs this research and will help the experts to better understand the nuances in Dering’s other canvases.

William Dering was a Williamsburg dancing master and portrait painter who navigated the upper echelons of Virginia society in the first half of the 18th century. The first record of him in the American colonies is in an advertisement for his dancing school in the Pennsylvania Gazette in 1735. In an notice in the same periodical a year later, he was offering a significantly wider array of teaching services, to wit “Reading, Writing, Dancing, Plain Work, Marking, Embroidery, and several other Works: where Likewise young Ladies and Gentlemen may be instructed in the French.”

He and his wife Sarah moved to Virginia and by November of 1737 he was in Williamsburg. An advertisement in the Virginia Gazette of November 25th announced that Dering had “opened his School at the College, where all Gentlemen’s Sons may be taught Dancing, according to the newest French Manner….” He appealed solely to the sons of gentlemen because his classes were held at the College of William of Mary which was then men-only.

What we know of Dering’s social life is the result of his friendship with the socially prominent statesman, planter and founder of Richmond, Virginia, Colonel William Byrd who kept extensive diaries recording his daily life. Dering was a regular visitor to his estate, Westover Plantation. One night on June 6th, 1740, Byrd noted Dering had joined him for dinner of bacon and greens followed by talking, a game of bowls and a walk. They shared many such pleasant evenings. Dering played the French horn during one of them.

Legal records paint a less carefree picture. Dering struggled to pay off multiple mortgages on his house next to the Governor’s Mansion on the Palace Green, a rather high-end address for a dancing teacher, and he was involved in other lawsuits with creditors. It seems he lived consistently beyond his means and his home had to be auctioned after his death in early 1751. It is still standing today and is preserved and administrated by the Colonial Williamsburg Foundation.


Books in Denmark library found to be poisonous

July 2nd, 2018

Researchers at the University of Southern Denmark have discovered that three of the volumes in the university’s library rare books collection are poisonous. All three of them are history books. (Is it weird that that makes me inordinately proud?)

The books were not suspected of having killed a number of monks in a forbidding monastery in the Italian Alps. In fact, the study had nothing to do with identifying lethal literature. These three books were selected because they were known from previous investigation to have medieval manuscript fragments in their covers. Recycling old parchment was a common practice for bookbinders in the 16th and 17th centuries. Researchers aimed to use imaging technology to identify which Latin texts had been used to make the covers, or at least to recover legible passages.

The books were X-rayed, but the ink handwriting on the fragments was difficult to read through the thick layer of green paint on the outside of the covers. To break through the green barrier, the team tried using X-ray fluorescence analyses (micro-XRF) which is routinely used by painting conservators to analyze the chemical composition of pigments.

The idea was to filter through the layer of paint using micro-XRF and focus on the chemical elements of the ink below, for example on iron and calcium, in the hope of making the letters more readable for the university’s researchers.

But XRF-analysis revealed that the green pigment layer was arsenic. This chemical element is among the most toxic substances in the world and exposure may lead to various symptoms of poisoning, the development of cancer and even death. […]

The green arsenic-containing pigment found on the book covers is thought to be Paris green, copper(II) acetate triarsenite or copper(II) acetoarsenite Cu(C₂H₃O₂)₂·3Cu(AsO₂)₂. This is also known as “emerald green”, because of its eye-catching green shades, similar to those of the popular gemstone.

Paris green is an intense, brilliant color that was resistant to fading. These qualities made it popular, especially in the 19th century when it was found in everything from oil paints to clothes dyes to artificial flowers and wreaths. When people realized their dresses were killing them in the second half of the 19th century, Paris green fell into disuse as an aesthetic option and went on to a new career as a pesticide and insecticide. Researchers believe it was for the latter purposes that the book covers were painted with Paris green likely in the 19th century.

It seems we aren’t likely to find out what medieval Latin manuscripts were diced up by the bookbinders any time soon.

Under certain circumstances, arsenic compounds, such as arsenates and arsenites, may be transformed by microorganisms into arsine (AsH₃) – a highly poisonous gas with a distinct smell of garlic. Grim stories of green Victorian wallpapers taking the lives of children in their bedrooms are known to be factual.

Now, the library stores our three poisonous volumes in separate cardboard boxes with safety labels in a ventilated cabinet. We also plan on digitising them to minimise physical handling. One wouldn’t expect a book to contain a poisonous substance. But it might.





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