First I've heard of them. Pretty interesting.
Check this out:
The earliest sails were not made from canvas but from woven grass, which had to be dipped in tannins in order to be toughened up. This resulted in a reddish-brown hue, which was carried on when canvas masts were invented. The bright crimson masts seen in Hong Kong’s harbor today still bear this historical hallmark.
That's a great example! I like looking at the different challenges cultures had when they created the same type of tech.
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First I've heard of them. Pretty interesting.
Check this out:
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