Colonel Percy Harrison Fawcett (1867-1925?) was a retired military engineer with a great interest in archaeology. Fawcett, who published a number of articles in The Occult Review, believed in the existence of Atlantis and was convinced that he could find a remnant of its advanced population(c) .Inspired by stories of lost cities in the Amazonian jungle he was convinced that Brazil had been the home to a city that had been a colony of Atlantis. His ambition was to discover the location of this city, which he referred to as ‘Z’, and so prove the reality of Atlantis. Alan Baker recounts[1031.121] how in 1924 Fawcett wrote to Lewis Spence outlining his theory that this lost city had been home to white-skinned refugees from Atlantis. Undaunted by an earlier failed expedition, in 1925 he led a second attempt, partly sponsored by the Royal Geographical Society, into the Matto Grosso and disappeared without trace(a). A book by David Grann, The Lost City of Z, was published in 2009. There is a film produced by and starring Brad Pitt as Fawcett and his search for Z on release now (2017) and also entitled The City of Z.
The Russian researcher, Oleg Dyakonov, has written an extensive paper(d) on Fawcett, his expeditions, achievements and his critics. It is in Portuguese, but translates well with Google.