The next big technological development in the world of string was to twist fibres together. The bow string on Otzi's bow was made of sinue fibres twisted together. This allows for a strong longer than the raw material, but also stronger. Much stronger. There more to twisting fibres than you might think tho. If you twist a set of fibres one way to make a cord, and do that a few times, then twist those cords together the opposite way. The twists work to keep the cord together.
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