I am reading Desert Solitaire by Edward Abbey, first published in 1968. Abbey tells of his time as a ranger in the Arches National Park in Southern Utah in the 1960ies. One chapter is dedicated to water and how a desperate hiker can find it. There is a myth about getting water out of a barrel cactus. He tells that the best you can get is a few drops of bitter liquid out of the green pulp, but the labor and the exasperation would make you sweat and expended far more water.

He goes on:

When you reach this point you are doomed. Far better to have stayed at home with the TV and a case of beer. If the happy thought arrives too late, crawl into the shade and contemplate the lonely sky. See those big black scrawny wings far above, waiting? Comfort yourself with the reflection that within a few hours, if all goes as planned, your human flesh will be working its way through the gizzard of a buzzard, your essence transfigured into the fierce greedy eyes and unimaginable consciousness of a turkey vulture. Whereupon you, too, will soar on motionless wings high over the ruck and rack of human suffering. For most of us a promotion in grade, for some the realization of an ideal.

My advice to hikers: When you go into the desert, carry at least one gallon of water per day per person.