The Sweet Track is an ancient causeway in the Somerset Levels, England. Built in 3807 or 3806 BC along an earlier structure, the Post Track, it was the oldest unearthed timber trackway in Northern Europe until the 2009 discovery of a 6,000-year-old trackway in Plumstead, London. It extended close to 2,000 metres (6,600 ft) across the now largely drained marsh between what was then an island at Westhay and a ridge of high ground at Shapwick. Various artefacts, including a jadeitite ceremonial axe head, have been found along its length. Construction was of crossed wooden poles, driven into the waterlogged soil to support a walkway that consisted mainly of planks of oak, laid end-to-end. The track was abandoned after 10 years of use, probably due to rising water levels. Following its discovery in 1970, most of the track has been left in its original location, with active conservation measures taken, including a water pumping and distribution system to maintain the wood in its damp condition. Some of the track is stored at the British Museum and a reconstruction of a section was built at the Peat Moors Centre near Glastonbury. (Full article...)
A zoom sequence illustrating the set of complex numbers termed the Mandelbrot set. Images of the set, which was defined and named by Adrien Douady in tribute to the mathematician Benoit Mandelbrot, may be created by sampling the complex numbers and determining whether the result of iterating for each sample point goes to infinity. Images exhibit an elaborate and infinitely complicated boundary that reveals progressively ever-finer recursive detail at increasing magnifications. Consequently, the Mandelbrot set has become popular outside mathematics both for its aesthetic appeal and as an example of a complex structure arising from the application of simple rules.
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