Once black clouds gathered in the distance, to pour out a cloudburst. The 1.5 gravity gave the wall of water that swept down the canyon a far greater force and velocity than it would have had on Earth and boulders the size of small houses were tossed into the air and shattered into fragments. But all the rain fell upon the one small area and not a drop fell at the caves.

One single factor was in their favor and but for it they could not have survived such intense, continual heat: there was no humidity. Water evaporated quickly in the hot, dry air and sweat glands operated at the highest possible degree of efficiency. As a result they drank enormous quantities of water⁠—the average adult needed five gallons a day. All canvas had been converted into water bags and the same principle of cooling-by-evaporation gave them water that was only warm instead of sickeningly hot as it would otherwise have been.