Materials · 1867

Dynamite

Nitroglycerin absorbed into clay, safe enough for construction.

Alfred Nobel patented dynamite in 1867. It made tunnels, canals, railways and mines far cheaper to dig, and funded the Nobel Prizes.

Arcs above join it to what it stood on, arcs below to what it led to. The bar places this stretch on the tree's whole timeline.

What it built on 1