What is the author's tone in The Great Railway Bazaar: By Train Through Asia by Paul Theroux?

The tone of the author is rather cynical. He manages to find fault or make jokes about almost all situations and people. The Japanese railroads are faulted as being too fast, clean and efficient. At this point, the author longs for the slow sleeper car he took in Madras and beyond, India. These same railroads are criticized for being noisy, and uncomfortable. The Direct-Orient Express is mocked for having no dining cars. The Turkish Railways are luxurious and efficient in first-class, but the author dwells on the lower-class sections that are mobbed by Turks and Western hippies. The author's complaints about various people and places in a sense are the driving force of the book that keeps things going, along with the trains that are moving forward.