George Hamlin explores the historical context, railroad traditions, and varying approaches to these safety devices. Changes and standardization mean that many of these long-standing railroad traditions are about to vanish. Join us. You will enjoy looking at the diversity in signal systems over the years! This was a free on-line public program of the National Railway Historical Society, Washington, D.C. Chapter, Inc. www.dcnrhs.org - The program first aired on 4-15-22.