The Atlantic system ran on two flows that both end somewhere students rarely guess. Silver went east — past Seville, past Amsterdam, all the way to China. People went west — and overwhelmingly not to North America. Set the dials, then check your instinct against the records.
The mountain, and the pull
Potosí opened in 1545, Zacatecas in 1546. Between 1500 and 1800 the Americas produced roughly 150,000 tons of silver — on the order of 80 percent of world output. Where it settled was decided by price, not by policy.
+100%
0% — no reason to move+140%
Ming China shifted taxation towards silver payment — the “single whip” reform — creating enormous state demand. Around 1600 silver bought roughly twice as much in China as in Europe.
What the dial cannot show. Potosí sat at 4,000 metres on a barren mountain and by 1600 held perhaps 160,000 people — comparable to London — fed entirely by imported food and coerced labour. The mita drafted men from villages across a vast catchment every year; the patio process poisoned them with mercury from Huancavelica. Communities hid people, fled, or paid substitutes.
Ten point seven million people landed. Where?
Set each slider to the share you think that region received. They are normalised to 100 percent as you go. Then reveal the voyage records.
The source. The Trans-Atlantic Slave Trade Database is built from surviving voyage records — ships’ papers, port registers, insurance filings. It is an artefact of the trade’s own bureaucracy, which is why the arithmetic exists at all.