An Illinois-based professor will be leading research into the cultural history of chocolate and how it turned into the global force it remains today.

Guest: Amir D. Aczel.

Most historians agree that the compass has its origins in ancient Chinese lodestones. It was not utilized for sea travel, however, until the Italians unleashed its formidable powers in the twelfth century. Amir D. Aczel, author of The Riddle of the Compass, joins us today on Focus to share the story of navigation through the ages and the impact that the rise of the compass made on history.