A new invention has arrived in Ankh-Morpork - a great clanging monster of a machine that harnesses the power of all of the elements: earth, air, fire and water. This being Ankh-Morpork, it's soon drawing astonished crowds, some of whom caught the zeitgeist early and arrive armed with notepads and very sensible rainwear.
Steam is rising over Discworld, driven by Mister Simnel, the man wi' t'flat cap and sliding rule who has an interesting arrangement with the sine and cosine. It is managed by Moist von Lipwig, charmer and scoundrel extraordinaire who is under pressure from the Patrician (not wanting to stand in the way of progress but rather harness it). Moist will have to grapple with gallons of grease, goblins and some very angry dwarfs if he's going to stop it all going off the rails.
Raising Steam is less absurd than many earlier Discworld novels. The world has moved on from the Middle Ages into something akin to Victorian times (that development was already ver pronounced in earlier Lipwig centric books), and Magic is a sidenote and not a major player. The story is ostensibly about technical progress but also includes other subjects that the modern society faces - the coexistence of multiple "races" (human, dwarf, troll, goblin et al.) whcih is a recurring issue, fundamentalists and terrorism.
The story is not a tour de force through the world, through ideas or through a character development like many earlier books of the series. It is more of a nice family outing with nothing much happening. The famous TP humour sometimes glimpses through, but is not a consistent feature. I also miss the depth of character (most notable in Vetinari and Vimes) that the earlier novels had. The main players fall short of their earlier very complex and differentiated build. The obervations of persons and events and the descriptions and statements (ranging from cynic to hilarious) that made it such a pleasure to read and re-read the Discworld novels have made way to a quite straightforward and at times heavy-handed storytelling.
I imagine that the novel will be not very satisfactory either to readers who are not familiar with the Discworld universe. There are many throwbacks to characters and events in the mythology that are not quire explained but are nice for a long time reader who is preparing to say goodbye to this world due to Sir Terry's progressing illness.
I really wanted to like this book, and I did enjoy reading it, but more out of nostagia for books past than because it is an outstanding read.