Nimrud lens

The Nimrud Lens

The lens on display in the British Museum
Material	Rock crystal
Size	Diameter: 38 mm (1.5 in) Thickness: 23 mm (0.9 in)[1][2]
Created	750–710 BC
Period/culture	Neo-Assyrian
Place	North West Palace, Room AB
Present location	British Museum, London
Identification	90959

The Nimrud lens is a 3000 year old piece of rock crystal, which was unearthed by Austen Henry Layard at the Assyrian palace of Nimrud, in modern-day Iraq.^[3] It may have been used as a magnifying glass, or as a burning-glass to start fires by concentrating sunlight. Assyrian craftsmen made intricate engravings, and could have used such a lens in their work.^[3] The discoverer of the lens noted that he had found very small inscriptions on Assyrian artefacts which he suspected had been achieved with the aid of a lens.^[1]

The slightly oval lens has been roughly ground and has a focal point about 110 millimetres (4.5 in) from the flat side.^[1][2] The surface of the lens has twelve cavities that were opened during grinding, which would have contained naptha or some other fluid trapped in the raw crystal. The lens is said to be able to focus sunlight although the focus is far from perfect. Because the lens is made from natural rock crystal the material of the lens has not deteriorated significantly over time.^[1]

Italian scientist Giovanni Pettinato of the University of Rome has proposed that the lens was used by the ancient Assyrians as part of a telescope, and that this explains their knowledge of astronomy (see Babylonian astronomy).^[3] Experts on Assyrian archaeology are unconvinced, doubting that the optical quality of the lens is sufficient to be of much use. The ancient Assyrians saw the planet Saturn as a god surrounded by a ring of serpents, which Pettinato suggests was their interpretation of Saturn's rings as seen through a telescope.^[4] Other experts say that serpents occur frequently in Assyrian mythology, and note that there is no mention of a telescope in any of the many surviving Assyrian astronomical writings.^[3]

The Nimrud lens is on display in the British Museum.

See also

• Visby lenses

References

1. ^ ^{a b c d} Layard, Austen Henry (1853). Discoveries in the ruins of Nineveh and Babylon: with travels in Armenia. G.P. Putnam and Co. pp. 197–8,674. http://books.google.com/?id=1KITAAAAYAAJ&pg=PA674&dq=british+museum+lens+layard#v=onepage&q=lens&f=false. 
2. ^ ^{a b} D. Brewster (1852). "On an account of a rock-crystal lens and decomposed glass found in Niniveh" (in German). Die Fortschritte der Physik (Deutsche Physikalische Gesellschaft). http://books.google.com/?id=bHwEAAAAYAAJ&pg=RA1-PA355&dq=niniveh+lens. 
3. ^ ^{a b c d} Whitehouse, David (July 1, 1999). "World's oldest telescope?". BBC News. http://news.bbc.co.uk/1/hi/sci/tech/380186.stm. Retrieved May 10, 2008. "If one Italian scientist is correct then the telescope was not invented sometime in the 16th century by Dutch spectacle makers, but by ancient Assyrian astronomers nearly three thousand years earlier. According to Professor Giovanni Pettinato of the University of Rome, a rock crystal lens, currently on show in the British museum, could rewrite the history of science. He believes that it could explain why the ancient Assyrians knew so much about astronomy." 
4. ^ "World's oldest telescope?". EXN Science Wire. June 29, 1999. Archived from the original on Sept. 29, 2007. http://web.archive.org/web/20070929091502/http://www.exn.ca/Stories/1999/06/29/63.asp. Retrieved 2008-05-10. "Pettinato believes the lens was used by Assyrian astronomers as a telescope more than three thousand years ago. They saw more in the night sky than was possible with the naked eye alone. For example, the Assyrians saw the planet Saturn as a god surrounded by a ring of serpents. Pettinato says that would be a logical assumption to make if they saw Saturn's rings through a primitive telescope." 

External links

• Oldest Optical Device? The Nimrud Lens

This article is about an item held in the British Museum. Object reference: ME 90959.