

"I could not help but photograph them," he says. Photographer Nick Brandt, who has a long association with east Africa – he directed the video for Michael Jackson's Earth Song there in 1995 – took a detour from his usual work when he discovered perfectly preserved birds and bats on the shoreline. Animals that become immersed in the water die and are calcified. Here, this has come from volcanic ash, accumulated from the Great Rift valley.

The lake takes its name from natron, a naturally occurring compound made mainly of sodium carbonate, with a bit of baking soda (sodium bicarbonate) thrown in. Temperatures in the lake can reach 60 ☌, and its alkalinity is between pH 9 and pH 10.5. Unless you are an alkaline tilapia ( Alcolapia alcalica ) – an extremophile fish adapted to the harsh conditions – it is not the best place to live. Perhaps the staff of New Scientist will see it when our time comes but, until then, Lake Natron in northern Tanzania does a pretty good job of illustrating Dante's vision. ACCORDING to Dante, the Styx is not just a river but a vast, deathly swamp filling the entire fifth circle of hell.
