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#1 bonanova



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Posted 06 March 2008 - 10:41 AM

They're fairly common now.

But back in the '60s, when they were introduced, photochromic
sunglasses - they turned dark in bright sunlight - made a bit of
a splash. Materials that behaved like that were quite uncommon.

But some bloke did the research and came up with the following,
rather amazing, piece of information. Photochromic materials
are reportedly several millenia old, dating to the time of Alexander
the Great. This is a summary of a piece that appeared in 1966
in the IEEE Spectrum technical magazine. What you're about to
read may astound you.

Most people think of photochromic materials as a recent invention.
But records indicate that this is not so. It is recorded that the soldiers
of Alexander the Great knew of a black substance which could be
ground into a powder, dissolved in water and then soaked into
swatches of cloth torn from their uniforms.

When tied around a soldier's wrist, and as the sun rose, then sat
high in the sky, and later set in the West, the cloth would change
colors in a subtle way. With practice, the unaided eye could discern
these color changes and from them deduce quickly the approximate
time of day. That invention became widely known as Alexander's Rag
Time Band.

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Vidi vici veni.

#2 Lost in space

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Posted 06 March 2008 - 11:16 AM

Should be in jokes me thinks, and now you have me thinking!
There should be a section for these.
Lets hope your post produces more.

Instant five star rating!
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#3 unreality


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Posted 06 March 2008 - 09:16 PM

Nice, bonanova. That's pretty sweet!
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