Originally Posted by Doug5150

Well, I ,,, uhhh.....

Look at it this way: car tires all used cotton for the casings, once upon a time.

That time being....... -back around the first world war.

After industrial methods for making polyester were developed, all the tire companies switched to it as soon as they could.

And then later, when nylon came along, many changed from polyester to that also--although many tires still use polyester for reasons not pertinent to bicycle bags (polyester isn't as strong as nylon, but polyester has better heat & chemical resistance).

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If you still insist: many antique car-tire advertisements I've seen specifically mentioned using Egyptian cotton.
What exactly made it better than other choices I don't know, but anyway.
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