Thursday, September 26, 6:30 p.m., How Coffee Explains The World, Gunn Memorial Library, Washington Depot. Free. Presented by Nick Benson, founder of Washington based Zero Prophet Coffee. To meet the burgeoning demand for coffee in developed economies, production has increased by 50 percent in the last 25 years, involving 150 million people worldwide in the coffee economy, from crop to cup. Coffee is now conservatively estimated to be the world's fourth most-valuable agricultural commodity. To register, call 860-868-2310 or visit www.gunnlibrary.org.