Exploration Fawcett [clearly, from the evidence of this link, there's also a whacko fringe Fawcett-cult] - I can't put it down. Imagine Poe's Pym novel, except in real life, with a great deal more of detailed description & episodes, & the wisdom of experience & humane spirit. It ends with Fawcett's disappearance in the depths of the Amazon jungle. Notebooks compiled by his son - who is looking out his office window in the railroad yard in Lima Peru at the very railroad car his father was riding into the Andes (on his first expedition) the day he (his son) was born, back in London. Very Poe/Borgesian touch, there.
The Amazon (along with Vallejo & the Andes) creeps into the final passages of Forth of July - mingled strangely with The Countess from Minneapolis (ps. that cover image is a painting of Hennepin Ave) & Pushkin's short story "The Queen of Spades".
"...by the shores of great rivers" (Mandelstam)