Some stuff you can't make up. While preparing for the Trinity test, the workers were concerned that while hoisting the five ton bomb to the top of the 100 foot tower that bad things could happen.
There was never a concern that the bomb would detonate, but some of the new technology was rather delicate and they didn't want anything to break if for some reason the hoisting chain failed.
So they brought in a truckload full of...mattresses to stack on the ground below while the plutonium bomb was raised to the platform.
You can't make some stuff up.
