As the ball of magma cools, it forms a hard skin, cold on the outside where it faces the universe.
The skin jostles on currents, fluid and warm but hidden in darkness.
They grind and chip each other, the flakes of skin, teeth gnashing at the edges, fingernail against fingernail.
The stubborn ones keep pushing, deforming each other into hills and valleys, ridges like a sheetmetal car crash but more slow.
As these skin pieces grind, water falls and collects, moves from the higher places to the lower—and the harder, more sudden, its turn, the more skin it bears away in dust and pebble.
As the skin pieces grind, warm air rises and is replaced by neighboring air. Where skin stands high and jagged, the breeze gathers its force blasting away particles.
Plants step in to mediate the confrontation—they hold the rocks and pebbles and dust where it has been dropped while letting the wind and water jostle branches and leaves. These great colonizers march slowly from place to place.
People gather near the plants where they are thickest. They move where the food is.
At a bend in a river, inside a curve where floods don't rise as fast, people gather from time to time when fording is easy. They meet each other and celebrate marriage and the deities.
Random foragings abandoned by the river grow. The camp becomes permanent and marks land to be planted.
The herders still move through the territory on paths now becoming worn. Villages pop up at path intersections, defensible hills, other river bends, the density determined by the carrying capacity of the territory's plants.
The original camp triumphs and is destroyed, triumphs and is destroyed, countless times in its search to monopolize grain land. The herders come through picking new paths through the ruins, setting an ordered network for the next triumph. Cows find the shortest shallowest routes.
The people spill outside of the walls, especially if they make smelly or loud things. From the city gate, settlement extends like fingers along roads.
Warehouses become factories, water wheels become smokestacks. Surface area nurtures commerce.
The city walls come down since death is no longer delivered horizontally.
The commons are enclosed, tractors replace human labor, population grows until the countryside casts it off, unable to support it with wages. The city doubles, triples, quadruples in size. Disorganized accommodation.
New roads are faster than the river and take those who can leave out of the city.