Roman builders worked intensively with concrete and developed mixtures with durable and partly self-healing qualities. Later societies could lose that expertise when the practice, materials, and unwritten craft knowledge no longer continued together. The modern counterpart is moving from Crossrail to another major rail project before specialist teams disperse. Keeping people employed across successive projects can preserve a knowledge base more cheaply than rebuilding it from documents after a long break. Technological continuity depends on institutions and trained communities as well as surviving formulas.
Notable Point · 2:00:34-2:01:56
Roman concrete and Crossrail show why technical skills need continuity
Ancient concrete and modern rail construction become paired examples of knowledge improving through repeated practice and decaying when a trained workforce disperses.