Cleopatra's Tears (Big River Trilogy #2), by Harry Stephen Keeler (epub/Kindle/pdf)

Several men find themselves stranded by a flooding river on Bleeker’s Island. The jewels known as Cleopatra’s Tears are missing, and one of the men is believed to be Actor Hart, notorious killer and thief -- maybe even the one who stole the jewels. Can the sheriff figure out which one is Hart -- and make sure he’s the one without a life jacket when the dam upriver gives way?