by David Braun
In the journal Nature, the team reported that it has also discovered carbon nanotubes in the sword—the first nanotubes ever found in steel, Paufler says. The nanotubes, which are remarkably strong, run through the blade’s softer steel, likely making it more resilient.
“It is a general principle of nature,” Paufler said. “Materials that are softer, you can strengthen by including harder wires.”
Secret Sword Techniques
Some of the nanowires Paufler and his team had previously found were made of an extremely hard iron-based mineral called cementite. In the new research, the team discovered that carbon nanotubes encase some cementite nanowires, protecting them. These nanotube-nanowire bundles may give the swords their special properties, Paufler says.
The bundles run parallel to the blade’s surface and may help larger particles of cementite arrange in layers. These hard layers, which have softer steel in between, could help explain how the steel remains strong yet flexible. This combination of strength and flexibility makes the steel ideal for forging swords.
The blades were generally made from metal ingots prepared in India using special recipes, which probably put just the right amount of carbon and other impurities into the iron. By following these recipes and following specific forging techniques, “craftsmen ended up making nanotubes more than 400 years ago,” Paufler and his colleagues wrote.
“The important fact is that nanotubes were serving some very useful purpose even before they were discovered. This should inspire us to look for new practical applications of these remarkable nanostructures.”
Andrei Khlobystov
chemist, University of Nottingham, U.K.
When these blades were nearly finished, blacksmiths would etch them with acid. This brought out the wavy light and dark lines that make Damascus swords easy to recognize. But it could also give the swords their sharpness, Paufler says. Because carbon nanotubes are resistant to acid, they would protect the nanowires, he theorizes. After etching, many of these nanostructures could stick out from the blade’s edge, giving it tiny sawlike teeth.
Skeptical Smiths
The techniques for making the steel were lost around A.D. 1700. But many researchers are studying how to re-create the blades—evens though metallurgical experts warn that the blades, though exceptional for their time, are far outperformed by modern steels.
While some scientists have claimed success, others dispute that the reproductions are truly the same as the originals. And many experts doubt that the new findings will clear things up. John Verhoeven, a metallurgist at Iowa State University at Ames who has worked on reproducing the Damascus sword-making techniques, is skeptical that Paufler and his colleagues have cracked the secret of Damascus blades. “I don’t think that [the nanowires] are anything unusual,” Verhoeven said. “I think those structures would be found in normal steels.”
The Damascus sword is also an example of how unexpected nanosize structures can show up in materials—and sometimes give them surprising properties, experts say. But not all these nanoproperties are good. Asbestos, for example, comes in needlelike particles that cause severe lung disease. Break these particles into shorter pieces, and they are much less harmful. Because of nanomaterials’ unpredictable behavior, several researchers asked for more studies of these materials and their potential side effects.
TRUTH:
DAMASCUS SWORDS HAVE DISTINCTIVE-LOOKING BLADES THAT ARE CHARACTERIZED BY INTRICATE PATTERNS THAT RESEMBLE OIL SLICKS AND FLOWING WATER.
HIDDEN HOLTUN
Lost City Revealed
Under Centuries of Jungle Growth
Something big is hiding in the jungle, and archaeologists say it’s nearly a hundred ancient Maya buildings detected under a Guatemalan rain forest.
Hidden for centuries, the ancient Maya city of Holtun, or Head of Stone, is finally coming into focus. Three-dimensional mapping has “erased” centuries of jungle growth, revealing the rough contours of nearly a hundred buildings, according to research presented in 2011.
Electronic Archaeology
Though it’s long been known to locals that something is buried in this patch of Guatemalan rain forest, it’s only now that archaeologists are able to begin teasing out what exactly Head of Stone was.
Using GPS and electronic distance-measurement technology in 2010, the researchers plotted the locations and elevations of a seven-story-tall pyramid, an astronomical observatory, a ritual ball court, several stone residences, and other structures.
The Maya Denver
Some of the stone houses, said study leader Brigitte Kovacevich, may have doubled as burial chambers for the city’s early kings. “Oftentimes archaeologists are looking at the biggest pyramids or temples to find the tombs of early kings, but during this Late-Middle Preclassic period”—roughly 600 to 300 B.C.—“the king is not the center of the universe yet, so he’s probably still being buried in the household,” said Kovacevich, an archaeologist at Southern Methodist University in Dallas.
TRUTH:
THE MAYA OFTEN LEFT OFFERINGS, SUCH AS JADE OR CERAMICS, AT THE BASE OF THE ASTRONOMICAL OBSERVATORIES.
“That may be why so many Preclassic kings have been missed” by archaeologists, who expected to find the rulers’ burials at grand temples, she added.
The findings at Head of Stone—named for giant masks found at the site—could shed light on how “secondary” Maya centers were organized and what daily life was like for Maya living outside of the larger metropolitan areas such as Tikal, about 22 miles (35 kilometers) to the north, according to Kathryn Reese-Taylor, a Preclassic Maya specialist at Canada’s University of Calgary.
Head of Stone, which has never been excavated, “was not a New York or Los Angeles, but it was definitely a Denver or Atlanta,” said Reese-Taylor, who called the new mapping study “incredibly significant.”
Head of Stone 101
The ancient Maya city of Holtun, which means “Head of Stone,” is a modest site from the Pre-Classic period (600 B.C. to A.D. 250). The city had no more than 2,000 people at its peak, and preceded the famous large city-states and kingship culture for which the Maya are popularly known.
Buried Pyramid
From about 600 B.C. to A.D. 900, Head of Stone—which is about three-quarters of a mile (1 kilometer) long and a third of a mile (0.5 kilometer) wide—was a bustling midsize Maya center, home to about 2,000 permanent residents. But today its structures are buried under several feet of earth and plant material and are nearly invisible to the untrained eye.
Even Head of Stone’s three-pointed pyramid—once one of the city’s most impressive buildings—“just looks like a mountain enveloped in forest,” said study leader Kovacevich, who presented the findings at a meeting of the Society for American Archaeology in Sacramento, California.
Jungle Thick as Thieves
Head of Stone is so well hidden, in fact, that archaeologists didn’t learn of it until the early 1990s, and only because they were following the trails of looters who had discovered the site first—perhaps after farmers had attempted to clear the area, according to Kovacevich.
For thieves, the main attractions were massive stucco masks measuring up to 10 feet (3 meters) tall. Uncovered as looters dug tunnels into the buried city, the heads once adorned some of Head of Stone’s most important buildings.
The temple, Kovacevich said, “would have had these really fabulously, elaborately painted stucco masks flanking the two sides of the stairway that represented human figures, snarling jaguars,” and other forms.
During the Preclassic period, Head of Stone’s important public buildings would have been painted primarily in blood reds, bright whites, and mustard yellows, the University of Calgary’s Reese-Taylor said. Murals of geometric patterns or scenes from myth or daily life would have covered some of the buildings, she added.
“Little is known about how kingship developed, how individuals grabbed political power within the society, how the state-level society evolved and why it th
en was followed by a mini-collapse between 100 A.D. and 250 A.D.”
Brigitte Kovacevich
archaeologist, Southern Methodist University
King of Stars
During special events at Head of Stone, such as the crowning of a king or the naming of a royal heir, “there would have been a lot of people—not only the 2,000 people living at the site itself but all the people from surrounding areas as well. So, several thousand people,” Reese-Taylor said.
Thick gray smoke and the smell of burning incense would have filled the air. Gazing up at the temple top through this haze, a visitor might have seen “ritual practitioners” performing dances and sacred rituals while adorned with elaborate feathered costumes and jade jewelry.
During the solstices or equinoxes, the crowds would have moved farther south and higher up in the city, surrounding the buildings that made up the astronomical observatory. “During the solstices, you would’ve been able to see the sun rising in line with the eastern structure, and the common people would have thought that the king was commanding the heavens,” study leader Kovacevich said.
The researchers, though, are directing their gaze downward. Soon they hope to begin excavating residential structures and the observatory, as well as to possibly remove the undergrowth from the main temple.
And, by using ground-penetrating radar, they hope to bring Head of Stone into even sharper relief. By seeing through soil the way the previous mapping project saw through trees and brush, radar should reveal not just the rounded shapes of the city but also the hard outlines of the buildings themselves.
TRUTH:
ALMOST ALL MAYA SITES HAD A RITUAL BALL COURT.
“WONDER”FUL WORLD
The Seven New Wonders of the World
The Seven Wonders of the Ancient World have been joined by seven new wonders of the world, selected by popular vote and announced in 2007.
In 1999 the New7Wonders Foundation—the brainchild of Swiss filmmaker and museum curator Bernard Weber—decided to have a global contest to create a new list of man-made marvels that would join the classic Seven Wonders of the Ancient World, which were picked by Greek scholars about 2,200 years ago. The goal of the modern competition? To “protect humankind’s heritage across the globe.”
Yet the competition sparked controversy, drawing criticism from the United Nations’ cultural organization UNESCO, which administers the World Heritage sites program. “This initiative cannot, in any significant and sustainable manner, contribute to the preservation of sites elected by [the] public,” UNESCO said in a statement.
Runners-Up
Unsuccessful candidates included:
1. The giant statues of Easter Island in the Pacific Ocean
2. The Kremlin in Moscow, Russia
3. The Sydney Opera House in Australia
Getting Out the Votes
Regardless of other opinions, the New7Wonders competition was on and the voting process began in 2005. Nearly 200 nominations that came in from around the world were narrowed down to 21. The winners were voted for by Internet and phone, American Idol style, and the foundation reported that nearly a hundred million votes were counted.
The winners: “Christ the Redeemer” statue in Rio de Janeiro, the Great Wall of China, the Colosseum in Rome, Jordan’s ancient city of Petra, the Inca ruins of Machu Picchu in Peru, the ancient Maya city of Chichén Itzá in Mexico, and India’s Taj Mahal.
WONDER 1
“Christ the Redeemer” statue, Rio de Janeiro
(Photo Credit 8.3)
Standing tall on Corcovado mountain, the 105-foot-tall (38-meter-tall) “Christ the Redeemer” was constructed between 1922 and 1931. The statue underwent a four-month restoration in 2010, when workers cleaned and replaced its stone exterior. Brazilian President Luiz Inácio Lula da Silva very openly campaigned for and encouraged his compatriots to vote for the mountaintop statue.
WONDER 2
Great Wall of China
This newly elected world wonder was built along China’s northern border throughout many centuries to keep out invading Mongol tribes. Constructed between the 5th century and the 16th century B.C., the Great Wall is the world’s longest man-made structure, stretching some 4,000 miles (6,400 kilometers). The best known section was built around 200 B.C. by the first emperor of China, Qin Shi Huang Di. When the new seven wonders were announced, the Chinese state broadcaster chose not to broadcast the event, and Chinese state heritage officials refused to endorse the competition.
(Photo Credit 8.4)
WONDER 3
The Colosseum, Rome, Italy
(Photo Credit 8.5)
The only finalist from Europe to make it into the top seven—the Colosseum in Rome, Italy—once held up to 50,000 spectators who came to watch gory games involving gladiators, wild animals, and prisoners. Construction began around A.D. 70 under Emperor Vespasian. Modern sports stadiums still resemble the Colosseum’s famous design. European sites that didn’t make the cut include Stonehenge in the United Kingdom; the Acropolis in Athens, Greece; and the Eiffel Tower in Paris, France.
WONDER 4
Petra, Jordan
Perched on the edge of the Arabian Desert, Petra was the capital of the Nabataean kingdom of King Aretas IV (9 B.C. to A.D. 40). Petra is famous for its many stone structures, such as a 138-foot-tall (42-meter-tall) temple with classical facades carved into rose-colored rock. The ancient city also included tunnels, water chambers, and an amphitheater, which held 4,000 people. The desert site wasn’t known to the West until Swiss explorer Johann Ludwig Burckhardt came across it in 1812.
(Photo Credit 8.6)
(Photo Credit 8.7)
WONDER 5
Machu Picchu, Peru
One of three successful candidates from Latin America, Machu Picchu is a 15th-century mountain settlement in the Amazon region of Peru. The ruined city is among the best known remnants of the Inca civilization, which flourished in the Andes region of western South America. The city is thought to have been abandoned following an outbreak of deadly smallpox, a disease introduced in the 1500s by invading Spanish forces. When the new seven wonders were announced, hundreds of people gathered at the remote, 7,970-foot-high (2,430-meter-high) site to celebrate Machu Picchu’s new “seven wonders” status.
WONDER 6
Chichén Itzá, Mexico
Chichén Itzá is possibly the most famous temple city of the Maya, a pre-Columbian civilization that lived in present-day Central America. It was the political and religious center of Maya civilization during the period from A.D. 750 to 1200. At the city’s heart lies the Temple of Kukulkan—which rises to a height of 79 feet (24 meters). Each of its four sides has 91 steps—one step for each day of the year, with the 365th day represented by the platform on the top.
(Photo Credit 8.8)
THE SEVEN WONDERS OF THE ANCIENT WORLD ARE:
1. THE GREAT PYRAMID OF GIZA, EGYPT. The Egyptian pharaoh Khufu built the Great Pyramid in about 2560 B.C. to serve as his tomb. It is the only remaining monument from the original list.
2. THE COLOSSUS OF RHODES, GREECE. The massive statue of the Greek sun god Helios took 12 years to build. Completed in 282 B.C., the Colossus was felled by an earthquake that snapped the statue off at the knees a mere 56 years later.
3. THE LIGHTHOUSE OF ALEXANDRIA, EGYPT. Built on the small island of Pharos between 285 and 247 B.C., the lighthouse stood for more than 1,500 years before earthquakes seriously damaged it in 1303 and 1323.
4. THE STATUE OF ZEUS AT OLYMPIA, GREECE. Created around 432 B.C., the 40-foot-tall (12-meter-tall) gold statue honored the original Olympic Games. Centuries later the statue was destroyed, although historians are still uncertain as to how.
5. THE HANGING GARDENS OF BABYLON, IRAQ. The Babylonian king Nebuchadnezzar II supposedly created the gardens around 600 B.C. to please his wife. It is believed they stood on the banks of the Euphrates River, but the exact location is unknown.
6. THE MAUSOLEUM OF HALICARNASSUS, TURKEY. T
he enormous tomb was built between 370 and 350 B.C. for King Mausolus of Caria, a region in the southwest of modern Turkey. The mausoleum stood intact until the early 15th century.
7. THE TEMPLE OF ARTEMIS, TURKEY. Completed around 550 B.C., the marble temple was burned down in 356 B.C. It was restored, only to be destroyed by the Goths in A.D. 262 and again by the Christians in 401 on the orders of St. John Chrysostom, then archbishop of Constantinople (Istanbul).
(Photo Credit 8.9)
WONDER 7
Taj Mahal, India
The Taj Mahal, in Agra, India, is the spectacular mausoleum built by Muslim Mughal Emperor Shah Jahan to honor his beloved late wife, Mumtaz Mahal.
Construction began in 1632 and took about 15 years to complete. The opulent, domed mausoleum, which stands in formal walled gardens, is generally regarded as the finest example of Mughal art and architecture. It includes four minarets, each more than 13 stories tall. Shah Jahan was deposed and put under house arrest by one of his sons soon after the Taj Mahal’s completion. Its said that he spent the rest of his days gazing at the Taj Mahal from a window.
ANCIENT SHOES
120 Ancient Roman Shoes