At last, after a weary week, the day had come and the hour. I ask you to picture the shaded sitting room of the Fazenda St. Ignatio, two miles inland from the town of Manaus. Outside lay the yellow, brassy glare of the sunshine, with the shadows of the palm trees as black and definite as the trees themselves. The air was calm, full of the eternal hum of insects, a tropical chorus of many octaves, from the deep drone of the bee to the high, keen pipe of the mosquito. Beyond the veranda was a small cleared garden, bounded with cactus hedges and adorned with clumps of flowering shrubs, round which the great blue butterflies and the tiny hummingbirds fluttered and darted in crescents of sparkling light. Within we were seated round the cane table, on which lay a sealed envelope. Inscribed upon it, in the jagged handwriting of Professor Challenger, were the words:⁠—