The word Lens is derived from a Latin word, Lanes, which is Latin for lentil. This name was applied to the object,

to which it was applied, because if you look at a double convex lens, that is a lens that bows

outward in the middle on both sides, if you look at such a lens side-on, it is shaped kind of like

a lentil is shaped. There's some evidence that lenses in various

forms made of various materials and used for various applications have been around for perhaps

thousands of years, maybe even as far back as the 7th century BC, a time period from once

a polished rock crystal, sometimes called the

Nimrod Lens, because of where it was discovered, a place in Iraq, formerly called Nimrod,

back in the region's Assyrian days, but which is also sometimes called the Laird Lens,

which is a name derived from its discoverer, an English archaeologist,

world traveler, cuneiform expert, politician, beer maker, and all-around interesting fellow

named Austin Henry Lalyard. He discovered this stone and posited alongside other experts

that it may have been used as a light-focusing lens,

meant to capture sunlight, focus it to a point, and as a consequence, start fires.

There's also a chance that it was used as a magnifying lens by craftsmen working on fine details

in their metalwork to ensure that they could clearly see the

intricate illustrations that they were etching into their products.

There is a decent amount of doubt about this, and other contemporary maybe lenses from this period,

including those that were maybe used by ancient Egyptians.

So keep that in mind when you hear talk about lenses being around for that duration.

It's not a certain thing, even if it's kind of neat to think about.

But historians are a lot more certain about the intent and use cases for the highly polished

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