Here are relevant parts that influenced Jerry and I, along with one I missed. Having read a history of the Lewis and Clark expedition the significance is huge.
Iron Ratioins
If the worst happened, this would be their iron rations for a desperate time. If nothing happened, it would all keep. He selected a jar of English beef tea, a sealed package of bouillon cubes, a jar of Swiss chocolates and a sealed tin of hard candies, a canned Italian cheese, and a few other small items.
WB note included a jar of instant coffee, non-dairy creamer, and at least one box of sugar cubes.
He never had enough fats, or sweets, or starches, and the greater part of each day was usually spent in physical effort of one kind or another
WB note - the Lewis and Clark history noted how the men ate YUGE amounts of meat and stayed hungry. Once they were at their Ft in Oregon and could get fats, starches, and sugars (honey) their hunger was more or less eliminated.
WB Note - SALT influence. Several pages were devoted to this part.
In August they ran out of salt, armadillos destroyed the yam crop, and the fish stopped biting. That terribly hot August was the month of disaster.
The end of the corn and exhaustion of the citrus crop had been inevitable. Armadillos in the yams was bad luck, but bearable. But without fish and salt their survival was in doubt.
As soon as they were out of salt it seemed that almost everything required salt, most of all the human body. Day after day the porch thermometer stood at ninety-five or over and every day all of them had manual labor to do, and miles to walk. They sweated rivers. They sweated their salt away, and they grew weak, and they grew ill. And all of Fort Repose grew weak and ill for there was no salt anywhere.
Attached is the word doc conversion/edit of Alas Babylon. I'd suggest this one over the .pdf