 And then you build your, you know, 140-foot-high gas bag out of it. So these are enormously fragile, and they're containing one of the most explosive substances on Earth. And it was very retro in a way, and nobody actually figured it out until Goodyear did later in the 30s. They finally figured out some kind of a rubberized backing that would do this. But until then, this was part of the bargain of the airship. They did...