I had been anticipating this book for a while as Terry Pratchett is one of my favourite authors, and I have enjoyed most, but not all, of Stephen Baxter's books.They have taken the concept of parallel earths and devised a nifty device called a stepper, incorporating a potato (the Pratchett influence) to enable people to step between them. Most people when stepping suffer nausea shortly after stepping, by Joshua, the main character, is a natural stepper who can move swiftly without these effects, or as he discovers without using the stepper. His talents are noticed by a computer entity called Lobsang, who helps him out with a little problem that he had with the authorities.Lobsang proposes to travel to ends of the Long Earth with Joshua in a dirigible. Along the way they discover all types of alternative humanities, and humans who have settled far from earth, and discover things about themselves before reaching the very end an something that they were not expecting.I kind of enjoyed reading it, but I didn't think that the plot was that strong, and the ending was fairly weak. The writing is fairly seamless given that they write in such different ways normally.