Metropolitan Diary: Volunteer Traffic Director Dear Diary: Once again, I was visiting New York, a city that has amazed me since childhood, when family vacations to visit Pennsylvania relatives sometimes included a couple of days in Manhattan. During my most recent visit, strolling along Broadway in Midtown one weekday afternoon, I couldn't help noticing a Fire Department ambulance hopelessly stalled in gridlock on a side street, siren blaring, emergency lights flashing. "Wait a second," I told my companion, "this could be interesting." Quickly, a middle-aged man in a business suit emerged from the sidewalk crowd and walked onto Broadway. Upon reaching the center of the signalized intersection, he set his briefcase at his feet. His arms now free, he signaled Broadway traffic to a halt in both directions. Now heeding his direction, not the red light, drivers quickly cleared the side street, opening the intersection for the emergency vehicle. The ambulance turned left and proceeded up Broadway. The anonymous good Samaritan retrieved his briefcase, exited the intersection and walked off. I felt like we bystanders should have applauded his decisive action which, who knows, may have helped save a life. Read all recent entries and our updated submissions guidelines. Reach us via e-mail: diary@nytimes.com or telephone: (212) 556-1333. Follow @NYTMetro on Twitter using the hashtag #MetDiary.