Victoria Falls rainbows. 19th-century illustration of a double rainbow formed by sunlight refracting through spray and mist produced by Victoria Falls, on the Zambezi River in southern Africa. This waterfall, one of the world's largest, is 1708 metres wide and 108 metres tall. It is known locally as Mosi-oa-Tunya ('the Smoke that Thunders'). This illustration is by British artist Thomas Baines (1820-1875), who documented the scenery, flora and fauna of southern Africa from 1857 to 1864. In 1858 and 1859 he travelled with British explorer David Livingstone along the Zambezi River, visiting Victoria Falls and the surrounding areas.