Lost knowledge: ropes and knots
"Few realize the importance that knots and cords have played in human history. It is remarkable that they are not even mentioned in otherwise great books on the history of technology."
tools
"Few realize the importance that knots and cords have played in human history. It is remarkable that they are not even mentioned in otherwise great books on the history of technology."
Boring is quite interesting - how hole-making tools have evolved.