I've recently been carefully working my way chronologically through the discworld books, but I got a short loan of this one and couldn't pass it up, despite being nowhere near its turn. It is very different to the earliest books, perhaps lacking rather a lot of their laugh-after-laugh humour, but it wins out on one point. The whole book was justified for me by the staggeringly re-readable account of a man literally breaking the laws of the universe in order to read to his son at the appointed time. If the rest of the book were only a scene-setter for this, it would be worth it. Walking around for days after finishing it telling all and sundry that "It goes hrrugh, it is a hippopotamus" is surely a sign that a book is worth reading!