Watch Ghost Hunters season 4 episode 15 online for free. Jason and Grant are called in to investigate a haunt hidden in their own neighborhood â€” the Slater Mill. In its early years, almost all of the employees at the mill were children, and the workers were often pushed to their limits. Working conditions were difficult and unhealthy â€” respiratory ailments and diseases were rife, and the mill was home to many grisly accidents.Then, TAPS goes to Connecticut to unravel the mysteries at the historic Pettibone Tavern. Built in 1780, the tavern originally served as a carriage stop between Albany and Boston during the late 18th century. During this time, it was also supposedly the site of a brutal axe murder, and through the years, employees have consistently reported activity that they cannot explain.