Techniques and instruments that were once in use and later abandoned, misplaced or superseded.
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The Antikythera Mechanism is the earliest surviving geared device known to model astronomical and calendrical cycles.
Read full entryWardenclyffe was Nikola Tesla’s unfinished attempt to build a commercial global wireless station at Shoreham, Long Island.
Read full entry“Damascus steel” is an easy name for several different things, and much of its mystery begins there. Modern knife sellers often use the term for pattern-welded steel: layers of different…
Read full entryThe object popularly called the Baghdad Battery is a small ceramic vessel associated with Khujut Rabu, near ancient Ctesiphon in present-day Iraq.
Read full entryRoman concrete is not one universal miracle recipe. Roman builders produced different mortars and concretes for walls, vaults, foundations and marine works, adjusting lime, aggregate and…
Read full entryGreek fire was a real Byzantine incendiary system, but the familiar name can mislead. The people who used it called themselves Romans, and their texts used terms such as Roman fire, sea…
Read full entryPuma Punku is part of the Tiwanaku monumental complex on Bolivia’s high Altiplano, near Lake Titicaca. Today it appears as a field of displaced sandstone slabs and intricately shaped…
Read full entryIn crypts and chambers of the Temple of Hathor at Dendera, several reliefs show a serpent emerging from a lotus and extending inside a long oval form.
Read full entryThe Nazca Lines are not a single drawing or one-time project. They are a vast desert landscape of straight lines, trapezoids, spirals and figures representing animals, plants, humans and…
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Practices at the edge of accepted medicine — what has been studied, what has not, and where the record ends.
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Suppressed records, contested chronologies and the politics of what gets written down.
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Cosmologies, rites and symbol systems recorded across the ancient world.
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Figures that recur across mythologies — and the archaeology, hoaxes and folklore around them.
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