Scientific American Black Inventor Garrett Morgan Saved Countless Lives with Gas Mask and Improved Traffic Lights In 1916 he strapped on his “safety hood” and dragged rescuers to safety, but racism prevented him from being hailed as a hero Advertisement Just before midnight at the close of a hot summer day in 1916, a natural gas pocket exploded 120 feet beneath the waves of Lake Erie. It happened during work on Cleveland’s newest waterworks tunnel, a 10-foot-wide underwater artery designed to pull in water from about five miles out, beyond the city’s polluted shoreline. The blast left twisted conduit pipes littering the tunnel floor and tore up railroad tracks inside the corridor, with noxious smoke curling off the rubble. When the dust settled, 11 tunnel workers were dead.