For centuries slavers ravaged this coastline and sailed up the Congo river, and from the seventeenth to the nineteenth centuries one and a half million slaves were sent from here in a triangular trade that took slaves to the Americas, American cotton and sugar to Europe, and European goods to Africa. Slavers gave guns and money to local potentates, who ruled from colonial trading posts and drained the tribes of the interior, subverting local politics in ways that are eerily reminiscent of today’s oil trade.

Other curious similiarities exist. You can find one at Pointe Indienne, a quiet area of coastal bush and farmland, where bamboo thickets tumble down to a pretty beach and where onshore oil wells flare gas that lights up the bush and warm surf at night. . . . This was the regions main slave export point, and it was also at this very spot, in 1957, that oil was first found in Congo. Museum documents say they crammed three hundred to five hundred slaves per boat, making them dance to tone their muscles and to stop them slipping into “melancholy,” and a good male nègre à talent was worth the annual wage of a ship’s captain (females fetched 25 percent less). You can play mischievously with this data. Take a tanker captain’s wage today of, say, $100,000, multiply by 500, and this values a boatful of slaves at $50 million in today’s money — about the same as a million-barrel oil cargo.
(Poisoned Wells by Nicholas Shaxson, p.106-7, ISBN 978-1403971944)

It may be that one can make too much of this conjunction and comparison. Yet it certainly has symbolic resonance.