The title of the book refers to the Old Tolbooth prison in Edinburgh, Scotland, at the time in the heart of the Scottish county of Midlothian. The historical backdrop was the event known as the Porteous riots. In 1736, a riot broke out in Edinburgh over the execution of two smugglers. The Captain of the City Guards, Captain John Porteous, ordered the soldiers to fire into the crowd, killing several people. Porteous was later killed by a lynch mob...