Expect to see this on our streets soon, as we look for ways to run our motorized world on coal. Looks safe, too!
Mounted on the roof tops of English busses, balloonlike fabric bags are serving as reservoirs for coal gas, a fuel now in general use as a substitute for gasoline. In the photograph reproduced above, coal gas is being piped into the roof-top balloon reservoir of a bus before the vehicle starts off on a scheduled run.
Popular Science April 1940 via ::Modern Mechanix