Category Archives: History, sociology, and philosophy

Egyptian beads may have been made from meteorites

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Nature: Analysis of tube-shaped beads excavated from an ancient Egyptian cemetery has revealed the presence of iron with a high nickel content, which indicates the metal may have come from a meteorite. In their study published in Meteoritics and Planetary Science, Diane Johnson of the Open University in Milton Keynes, UK, and colleagues describe how they used scanning electron microscopy and computed tomography to study one of the beads. Not only did they find that the bead predates the development of iron smelting in the area, but they also observed that the metal displayed the distinctive crystalline structure known as a Widmanstätten pattern, found only in iron meteorites. The few iron artifacts that have been discovered have all come from the graves of important people, such as the pharaoh Tutankhamun, which suggests that the Egyptians recognized the celestial origin of the material.

Meteorite could have triggered past episode of climate change

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Telegraph: A period of significant global cooling called the  Younger Dryas, which occurred between 12 800 and 11 500 years ago may have been caused by a meteorite explosion and impact. James Wittke of Northern Arizona University and his colleagues examined carbon spherules from 18 archeological sites worldwide, dating to 12 800 years ago. They found that the spherules were formed by sediments melting at temperatures of 2200 °C. They compared them with similar spherules from volcanoes, lightning, and human sources and determined that the ones they found were caused by heat and shock waves from an object passing through and exploding in the atmosphere. They estimate that 10 million tons of the spherules were spread over an area of 49 million km2 as a result of the meteorite fragmentation. The dust and ash could have triggered the significant cooling that followed and that was partly responsible for the extinction of several species, including woolly mammoths, and for major changes in human behaviors.

America’s birthplace threatened by climate change

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NPR: What some consider to be the most important historical site in the US—Jamestown, Virginia—may disappear by the end of the century because of global warming. Jamestown, founded in 1607, was the first permanent English settlement in the Americas. Because it sits just above sea level, it is being threatened by the rising ocean, whose surface, climate scientists say, could swell by as much as 1 meter by 2100. The area has already suffered water damage: In 2003 Hurricane Isabel flooded Jamestown’s visitor center and glass factory, where present-day glassblowers replicate Old World techniques. The National Park Service is considering its options, which could involve levees and sea walls, all of which will be expensive. As many treasures there are still buried in the ground, archaeologists are debating whether to dig up everything while they still can.

Lidar used to find ancient city in Honduras

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Independent: A large, unmapped, densely forested area of eastern Honduras may be the site of an ancient city called Ciudad Blanca, first reported by Hernán Cortés in 1526. Cortés never found the city and neither have any subsequent explorers. Now Steve Elkins, a filmmaker and amateur archaeologist, has teamed with archaeologists from Colorado State University to use lidar to map part of the area. Lidar creates a 3D topological map of the ground and structures on it by firing billions of pulses of laser light that can penetrate the organic forest canopy. From data collected over one week, the researchers mapped a 155-km2 area, which revealed what may be a network of plazas and pyramids. Possibly dating back to 500 CE, the city also appears to have had paved roads, parks, and advanced irrigation systems. To prevent looting, the city’s precise location has not been revealed. In partnership with the Honduran government, Elkins plans to lead a ground expedition to explore the area and make a documentary film of the effort.

Acoustic imaging is used to map lost English city

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Spectroscopy Now: In 1286 a storm washed a large part of the English town of Dunwich into the North Sea and deposited significant amounts of silt in the mouth of the Dunwich River. Over the next 200 years, further storms continued to silt up the harbor and eat away parts of the city until most of the inhabitants abandoned the area. In the half-millennium since, most of the rest of the city has been washed into the sea. David Sear of Southampton University and his colleagues used high-resolution acoustic imaging technology to map the city’s underwater remains. Primarily used for imaging shipwrecks, the acoustic imaging was necessary because of the generally muddy nature of the water in the area. The imaging revealed that the city covered 1.8 km2, almost the area of present-day London. The coastal erosion that Dunwich experienced was due to storms that occurred during a period of significant global climate change. A better understanding of erosion processes caused by storms may help countries and towns prepare for potential effects of rising oceans and changing weather patterns due to global warming.

Optical technology used to play back old sound recordings

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Smithsonian: A wealth of early sound recordings made by Alexander Graham Bell and his assistants in the late 19th century have long remained “mute artifacts” because the method of playing them back was unknown. Now more than a century later, Bell’s voice has been heard for the first time. Researchers at the Smithsonian’s National Museum of American History, which holds a cache of more than 400 of Bell’s wax-and-cardboard disks and cylinders, teamed up with researchers at the Library of Congress and Lawrence Berkeley National Laboratory (LBNL). To create digital audio files of Bell’s recordings, LBNL researchers used the optical measurement technique they had developed to align the silicon detectors in the ATLAS experiment at CERN. They took multiple high-resolution images of the soundtracks, moving the camera in a spiral pattern to follow the path of the grooves, then used a computer to calculate the sound pressure waveform and used the data to create the audio file. The result was the sound of muffled voices reciting Hamlet’s soliloquy, number sequences, and “Mary Had a Little Lamb.” By deciphering notes scratched in wax on one of the disks, dated 15 April 1885, they discovered a recording of Bell himself. Perhaps reminiscent of Bell’s father, who was a renowned elocution teacher, Bell can now be heard making the ringing declaration, “In witness whereof—hear my voice, Alexander Graham Bell.”

Statistical methods may reveal cycles of history

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Wired: Cliodynamics is named for the Greek muse of history. Founded in the 1990s by Peter Turchin of the University of Connecticut, it is an attempt to mathematically explain cycles of history. With access to ever increasing amounts of historical data becoming available from all around the world and dating back thousands of years, Turchin and others are creating models to fit those data sets. Then they compare them with other data sets from other times and other cultures to see how well they fit. Turchin and his colleagues believe they have found a 100-year cycle of waves of instability that they call the Secular Cycle. They attribute the Secular Cycle to long-term demographic trends, such as populations exceeding production capacity, or a growing elite class competing for limited political and economic power. And in some countries, including the US, they see a secondary 50-year cycle of political violence that is associated with periods of growing social inequality. They explain these cycles as feedback loops like predator–prey cycles, not as rigidly defined rules of history. The cliodynamic approach to analyzing historical data has competition, but the general practice of applying statistical techniques to history is gaining acceptance by the wider historian community.

Turing’s Universal Machine chosen as greatest British innovation of the 20th century

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Telegraph: In the 1930s Alan Turing wrote a paper describing a machine that laid the mathematical groundwork for modern computing. Recently, Turing’s concept of a “universal computing machine” received 18% of the more than 50 000 votes in an online poll held as part of the UK’s National Science and Engineering Week. Second place went to the British Motor Corp’s Mini, and third place to x-ray crystallography, whose invention and applications led to several British Nobel Prizes. In a separate similar poll to choose “the innovation most likely to shape the 21st century,” voters selected ionic liquid chemistry.

Turkish physics professor tried for barring headscarves in classroom

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Science: Since the 1920s the Turkish constitution has banned the wearing of headscarves by women who work in the public sector. However, the ban has always been controversial, and since 2003 Turkey’s government has been dominated by a moderate Islamic political party, the Justice and Development Party. Now a senior astrophysics professor could go to prison for preventing female students wearing scarves from attending his class. Rennan Pekünlü, who teaches at Ege University in Izmir, claims he was upholding the Turkish constitution. Nevertheless, he was found guilty last September of violating the rights of women and faces 25 months in prison unless he wins his appeal next month. And he is not the only secularist academic having problems. In June of last year, Kemal Gürüz, the former head of Turkey’s Council of Higher Education and a prominent academic reformer, was arrested; Gürüz remains in prison.

Proto-language reconstructed by software?

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BBC: An international team of researchers has created a computer program that they believe can be used to help reconstruct the long-extinct precursors of modern languages. They used a database of 142 000 words and pronunciations from a collection of currently spoken Asian and Pacific languages and calculated probabilities of sound changes to calculate the parent language from which the current languages evolved. When compared to a parent language reconstructed by hand by linguists, 85% of the words in the computer generated language were within one sound difference of words in the linguist-constructed language. The benefit of the software is the large amount of data it can analyze quickly. However, that has to be balanced against its inability to recognize various quirks of language that make it less accurate than professional linguists.