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I was surprised when I was first made aware that Lake Tanganyika had no outlet in 1874. At about that time, however, tectonic activity changed local drainage systems. In 1876 Stanley determined (or at least he took credit for doing so) that the lake was draining by way of the Lukuga into the Congo. And wouldn't ya know it, fine readers, that pond on the hill let loose with ten meters of H2O over the next two-score years.