[1][2] At the age of eight, Jaffy Brown encounters a tiger escaped from the menagerie of Charles Jamrach, wandering about London's East End.

Several years later, when Jaffy is sixteen, he and Tim are dispatched by Jamrach to the Dutch East Indies, aboard a whaling ship.

Eventually Skip also dies, and by the time Dan and Jaffy arrive in Chile they are half-dead with exhaustion and half-mad from grief and anguish.

Charles Jamrach was a real historical figure who operated a menagerie in east London in the 19th century, and at one point a Bengal tiger escaped and took an eight-year-old boy in its mouth.

The ordeal of the crew in the lifeboats is largely based on the notorious shipwreck of the whaler Essex, which a sperm whale rammed and sank in 1820.