Back in 1931 Modern Mechanix magazine ran an article about an invention used by German firefighters to protect themselves from being engulfed in flames. The simple device consisted of a helmet with a built-in sprinkler system that connects with a nozzle on the hose. Using a hand lever, the firefighter could control the amount of spray needed for a given situation. Clever—but it seems that fighting a fire in something that looks like an old-timey deep sea diving helmet might prove problematic.