My mother worked in a war plant in the early 1940's. They made drop tanks out of cardboard that were then sprayed with several thin layers of rubber. After the rubber dried the cardboard would have to be removed from the inside. She said they used midgets or dwarfs to crawl inside the tanks and remove the cardboard. Does anyone know about this or have any photos. This happened in Akron and Canton Ohio, and she remembers seeing a picture of it.