Manhattan’s Noise Abatement Society began advocating for a quieter metropolis. Sympathetic to the society’s mission, a Bell Labs engineer named Harvey Fletcher created a truck loaded with state-of-the-art sound equipment and Bell engineers who drove slowly around New York City noise hot spots taking sound measurements. (The unit of measurement for sound volume—the decibel—came out of Fletcher’s research.) Fletcher and his team found that some city sounds—riveting and drilling
