Scientists develop new method for deciphering ancient scrolls

科学家开发出解读古代卷轴的新方法

The Vesuvius Challenge is an ongoing project that combines “digital unwrapping” with crowdsourced machine learning to decipher the so-called Herculaneum scrolls, badly charred 2,000-year-old papyri too fragile to be physically unrolled. The effort just got an additional boost. A team of researchers created their own contemporary model papyrus scrolls—charring them just like the originals—to validate a screening method to determine which of the Herculaneum scrolls were written in lead-based ink and hence are the most promising candidates for further analysis. They described the process in a new paper published in the journal PLoS ONE.

“维苏威挑战”（Vesuvius Challenge）是一个正在进行的项目，它结合了“数字展开”技术与众包机器学习，旨在解读所谓的赫库兰尼姆卷轴（Herculaneum scrolls）。这些卷轴是拥有2000年历史的莎草纸，因严重碳化而变得极其脆弱，无法通过物理方式展开。最近，这项工作获得了新的助力。一组研究人员制作了现代模型莎草纸卷轴，并像原始卷轴一样对其进行碳化处理，以验证一种筛选方法。该方法旨在确定哪些赫库兰尼姆卷轴使用了铅基墨水书写，从而成为进一步分析中最有希望的目标。他们在发表于《PLoS ONE》期刊的一篇新论文中描述了这一过程。

As previously reported, the ancient Roman resort town of Pompeii wasn’t the only city destroyed in the catastrophic 79 AD eruption of Mount Vesuvius. Several other cities in the area, including the wealthy enclave of Herculaneum, were fried by clouds of hot gas, called pyroclastic pulses and flows. But still, some remnants of Roman wealth survived. One palatial residence in Herculaneum—believed to have once belonged to a man named Piso—contained hundreds of priceless written scrolls made from papyrus, singed into carbon by volcanic gas. The scrolls stayed buried under volcanic mud until they were excavated in the 1700s from a single room that archaeologists believe held the personal working library of an Epicurean philosopher named Philodemus.

正如之前报道的那样，古罗马度假胜地庞贝城并非公元79年维苏威火山爆发中唯一被摧毁的城市。该地区的其他几座城市，包括富裕的赫库兰尼姆，都被称为“火山碎屑流”的高温气体云所焚毁。尽管如此，一些罗马文明的财富遗迹还是幸存了下来。赫库兰尼姆的一处宫殿式住宅（据信曾属于一个名叫皮索的人）中，藏有数百卷珍贵的莎草纸卷轴，它们被火山气体烧成了碳。这些卷轴一直埋在火山泥下，直到18世纪才被挖掘出来。考古学家认为，这些卷轴所在的房间曾是伊壁鸠鲁派哲学家菲洛德穆斯（Philodemus）的私人工作图书馆。

The few opened fragments helped scholars identify various Greek philosophical texts, including On Nature by Epicurus and several by Philodemus himself, as well as a handful of Latin works. But the more than 600 rolled-up scrolls were so fragile that it was long believed they would never be readable, since even touching them could cause them to crumble.

少数被打开的碎片帮助学者们识别出了各种希腊哲学文本，包括伊壁鸠鲁的《论自然》、菲洛德穆斯本人的几部著作，以及少量拉丁语作品。然而，那600多卷卷轴极其脆弱，长期以来人们一直认为它们永远无法被解读，因为即使是触碰它们也可能导致其碎裂。

Brent Searles’ lab at the University of Kentucky has been working on deciphering the Herculaneum scrolls for many years. He employs a different method of “virtually unrolling” damaged scrolls, which he used in 2016 to “open” a scroll found on the western shore of the Dead Sea, revealing the first few verses from the book of Leviticus. The so-called En Gedi scroll was recovered from the ark of an ancient synagogue destroyed by fire around 600 CE. To the naked eye, it resembled a small lump of charcoal, so fragile that there was no safe way to analyze the contents. The team’s approach combined digital scanning with micro-computed tomography—a noninvasive technique often used for cancer imaging—and segmentation to digitally create pages, augmented with texturing and flattening techniques. Then they developed software (Volume Cartography) to virtually unroll the scroll.

肯塔基大学的布伦特·西尔斯（Brent Searles）实验室多年来一直致力于解读赫库兰尼姆卷轴。他采用了一种不同的“虚拟展开”受损卷轴的方法，并于2016年成功“打开”了在死海西岸发现的一卷卷轴，揭示了《利未记》的前几节经文。这卷所谓的“恩戈地卷轴”（En Gedi scroll）是从一座约公元600年被火烧毁的古代犹太会堂的约柜中发现的。肉眼看去，它就像一小块木炭，极其脆弱，没有任何安全的方法来分析其内容。该团队的方法结合了数字扫描与微型计算机断层扫描（一种常用于癌症成像的非侵入性技术）以及分割技术，以数字方式创建页面，并辅以纹理化和展平技术。随后，他们开发了名为“体积制图”（Volume Cartography）的软件来虚拟展开卷轴。

Many of the inks used by Egyptian scribes contained large traces of metals, including lead, making them ideal for X-ray imaging. The older Herculaneum scrolls, however, were written with carbon-based ink (charcoal and water), so one would not get the same fluorescing in the scans; there is almost no difference in X-ray absorption between parts of the papyrus with ink and parts without ink. Searles was still able to capture minute textural differences, training an artificial neural network to do so.

埃及抄写员使用的许多墨水中含有大量的金属痕迹，包括铅，这使得它们非常适合X射线成像。然而，更古老的赫库兰尼姆卷轴是用碳基墨水（木炭和水）书写的，因此在扫描中无法获得同样的荧光效果；有墨水和无墨水的莎草纸部分在X射线吸收率上几乎没有区别。西尔斯仍然能够捕捉到细微的纹理差异，他为此训练了一个人工神经网络。

Looking for lead-based ink: Douglas Seiler, a retired inventor, was working with Berkeley SETI on a new telescope called Panoseti when he heard about the Herculaneum scrolls—as well as the poor signal-to-noise ratios that had been plaguing the efforts of Searles and others to digitally unwrap and decipher them. In 2016, scientists identified letters in two fragments of a scroll that contained lead, suggesting that some of the scrolls might be written in lead-based ink. So Seiler set out to test which of the scrolls were written with lead-based ink and put together an interdisciplinary team to help, including two retired Berkeley chemists and a Berkeley graduate student in archaeology with expertise in ancient Egyptian inks.

寻找铅基墨水：退休发明家道格拉斯·塞勒（Douglas Seiler）在与伯克利SETI合作开发一种名为Panoseti的新型望远镜时，听说了赫库兰尼姆卷轴，以及一直困扰西尔斯等人进行数字展开和解读工作的低信噪比问题。2016年，科学家在卷轴的两个碎片中发现了含有铅的字母，这表明部分卷轴可能是用铅基墨水书写的。因此，塞勒着手测试哪些卷轴是用铅基墨水书写的，并组建了一个跨学科团队提供帮助，其中包括两名退休的伯克利化学家和一名在古埃及墨水方面具有专长的伯克利考古学研究生。

The authors purchased modern Egyptian papyrus, which is still prepared in a similar fashion to the papyrus of two millennia ago, and traditional lampblack ink from Japan. They added different amounts of lead nitrate to the ink to create samples with different lead concentrations. A team of high school students inscribed the papyri with quotes from the Bible, Star Wars, and the 1960s TV show The Outer Limits, among other sources, using a reed stylus dipped in the different inks. The model scrolls were imaged with CT scans to verify the various lead concentrations. Then the team carbonized the scrolls in a high-temperature furnace to mimic the original Herculaneum scrolls, and co-author/physicist Jake LaManna created 3D X-ray scans of the charred models at NIST’s Center for Neutron Research in Maryland.

作者购买了现代埃及莎草纸（其制作方式与两千年前的莎草纸相似）以及日本传统的灯黑墨水。他们在墨水中添加了不同剂量的硝酸铅，以制作出具有不同铅浓度的样本。一组高中生使用蘸有不同墨水的芦苇笔，在莎草纸上抄写了来自《圣经》、《星球大战》和20世纪60年代电视剧《外星界限》（The Outer Limits）等来源的引文。模型卷轴通过CT扫描成像，以验证各种铅浓度。随后，团队在高温炉中对卷轴进行碳化处理，以模拟原始的赫库兰尼姆卷轴。合著者兼物理学家杰克·拉曼纳（Jake LaManna）在马里兰州的NIST中子研究中心对这些碳化模型进行了3D X射线扫描。

“The letters lit up like a Christmas tree,” said Seiler, adding, “It’s amazing what you can get electrons to do.” Co-author Michael Cyrus Daugherty, also of NIST, adapted a software program he’d written to unroll CT scans of so-called “jelly rolls” inside lithium-ion batteries to digitally unwrap the model scrolls and reveal the text. That’s good news for the Vesuvius Challenge, which made its first award for deciphering the first letters in 2023 and awarded the grand prize of $700,000 for producing the first readable text the following year.

“字母像圣诞树一样亮了起来，”塞勒说，并补充道，“你能让电子做出的事情真是令人惊叹。”同样来自NIST的合著者迈克尔·赛勒斯·多尔蒂（Michael Cyrus Daugherty）改编了他编写的一个软件程序，该程序原本用于展开锂离子电池内部所谓的“果冻卷”（jelly rolls）的CT扫描，现在被用来数字展开模型卷轴并揭示其中的文字。这对“维苏威挑战”来说是个好消息，该项目在2023年颁发了首个解读出字母的奖项，并在次年颁发了70万美元的大奖，以奖励首个成功解读出可读文本的团队。