Mark Twain was renowned for his ability to cast a spell over his readers with his words, wit and wisdom. His novels, The Adventures of Huckleberry Finn and Tom Sawyer, made him one of the world's most famous and best-loved authors.

Now, his autobiography has finally been made public - a hundred years after his death. And it reveals a very different side to the man known as America's national treasure, as Kathy Harcombe reports.