It was something to read, and it did have a certain historical value, being from the infamous Upton Sinclair, but other than its obvious propagandistic purpose the plot had no apparent aim. The characters were one-sided. The capitalists were pure evil, with no redeeming goodness. The socialists were harmless do-gooders, without vice nor venom. The story ends with a list of real-life travesties upon which the plot was based, accompanied by encouragement to request pamphlets and other publications from various left-leaning institutions. It's an excellent story if you've got nothing to do and nothing else to read.
This was a surprisingly worthwhile read. If you do read this one, do yourself a favor and read it with Google Maps open constantly. Also, the Wikipedia page about the author will give you a greater appreciation of the historical significance of the story. The charts that were originally in the story have been omitted from the electronic version, but they can be found pretty easily with an internet search. They're pretty necessary for understanding the complexities of navigation around the German coastline.
It was a very interesting story, over-all, though I think the main characters seemed intensely interested in investigating a tenuous thread that I probably would have ignored from the outset if I had been in their shoes. A man goes for a recreational ride in a yacht, and his pilot tries to get him killed on the sandy shoals. He spends the rest of the book trying to find out why.
The story had a nicely conceived plot that successfully delivered the ironic twist that it promised from the beginning. The writing style required a higher reading level, which is nice. At the end of the story, take note that it hints at (but never says) who Rouletabille's parents are, which goes toward explaining some of his behavior toward the principals.
Over-all, I give it one less than the full five stars only because the explanation of the mystery, though clever, is highly improbable. Still an enjoyable read, though.
Pinkerton's novels have a remarkable value, in that they show how detectives tracked down their targets without all of the technological advances that we have, today. The method, though placed somewhere near the time of Sherlock Holmes, is very practical and down-to-earth. After reading this, I realized what a bunch of fantasy-driven tripe that Sherlock Holmes really is!
The Expressman and the Detective involves a tremendous supply of detectives, surrounding and befriending the suspects, edging out all other friends, until eventually the truth is ascertained with a prosecutable certainty.