World's Oldest Telescope?
Is this the oldest telescope lens in the
world?
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.
But experts on Assyrian archaeology are unconvinced. They say
that the lens is of such low quality that it would have been a
poor aid to vision.
Magnifying glass
It is called the Nimrud lens and it was found in 1850 by the
legendary archaeologist Sir John Layard, during an epic series
of excavations at the palace of Nimrud in what is now Iraq.
Upon his return to England, he showed the lens to physicist Sir
David Brewer who thought it could have been used as a
magnifying glass or to concentrate the Sun's rays.
Used as a magnifying glass, it could have been useful to
Assyrian craftsman who often made intricate seals and produced
minuscule texts on clay tablets using a wedge-shaped
script.
It is a theory many scientists might be prepared to accept, but
the idea that the rock crystal was part of a telescope is
something else. To get from a lens to a telescope, they say, is
an enormous leap.
Saturn's serpents
Professor Pettinato counters by asking for an explanation of
how the ancient Assyrians regarded the planet Saturn as a god surrounded by a ring of
serpents?
Could they not have seen Saturn's rings through their telescope
and interpreted them as serpents? An unconvincing argument, say
experts. The Assyrians saw serpents everywhere. And why is it
in their many astronomical reports on clay tablets there is no
mention of such a device?
The conventional understanding of the invention of the
telescope is that it was developed in the 16th century by Dutch
spectacle-makers who held one lens in front of another.
One thing is sure: Galileo did not invent it - a common
misconception - although he was one of the first to turn it
towards the sky. By then, lenses used as spectacles had been
known for hundreds of years at least, and it has been a puzzle
to historians why it took so long for the telescope to be
invented.
Commercial and military use
It may have been developed and then forgotten, or even kept
secret. However, experts regard this as unlikely given the
commercial and military uses that a telescope could serve.
Whatever its origin, as ornament, as magnifying lens or part of
a telescope, the Nimrud lens is the oldest lens in the world.
Looking at it evokes mystery and wonder. It can be seen in room
55 of the British Museum, in case 9 of the Lower Mesopotamian
Gallery.
It may not be unique. Another, possibly 5th century BC, lens
was found in a sacred cave on Mount Ida on Crete. It was more
powerful and of far better quality than the Nimrud lens.
Also, Roman writers Pliny and Seneca refer to a lens used by an
engraver in Pompeii. So perhaps the ancients knew more about
lenses than we give them credit for.
by Dr. David
Whitehouse, BBC News Online Science Editor - July 1,
1999
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Source:
http://news.bbc.co.uk/2/hi/science/nature/380186.stm
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