Raising Steam (by Terry Pratchett)

(Amazon UK link) I have been re-reading the entire Discworld series, written by the brilliant Sir Terry Pratchett, over the past few years, at a rate of about one per month. I have just finished the fortieth book in the series, ‘Raising Steam’, which was published in 2014. I was given a copy for Christmas that year, and read it in April 2015. I remembered that it involved the Discworld invention and adoption of a railway, but nothing else. 
It opens with a general explanation about people becoming...