It mentions “the total amount of water in a man of average weight (70 kilograms) is approximately 40 liters”.
That could get you out of trouble if let’s say, you’re stuck in the middle of the Sahara. What do I need to get the water out of that sucker? I reckon a straw won’t do the trick. Will fire get me halfway there?
Some sort of solar still? Chop the cadaver into small pieces (you can probably drink the fluid in the eyeballs straight away, to keep you going while you work) Put the pieces in a pit (or a large container), cover with polythene and put a weight in the middle of the polythene to make a dip. Position a cup in the middle of the pit or container to catch the water dripping off the inside of the polythene.
Hell, just seal the corpse in an airtight container and I suspect after a month or two it’d be a skeleton with a nice layer of corpse water on top.
The trick would be getting pure water that was drinkable. As a macabre experiment I’d put the corpse through a high shear mixer, centrifuge the slurry, filter, then treat the supernatant with iodine to kill any living micro.
Ugly, messy, unethical (if one presupposes most religions’ rules for how to treat the dead). Also disgusting. But if you were living on Arrakis, maybe that practice would be standard.
Why? You can extract potable water from poisonous vegetation and piss and poop by means of a solar still. However, you will need to defend your still from predators looking to snack on the corpse. I don’t know how long it would take to dehydrate a corpse in the desert sun, nor do I know how much would be unextractable. This is the Straight Dope, however, and I expect someone here knows the answer.
I wouldn’t place too much reliance on a solar still, wiki says, and I’ve heard that although it’s always talked about in survival school, those that actually tried it would agree http://en.wikipedia.org/wiki/Solar_still
‘Knowing how to put together a solar still is often billed as a useful survival skill and could provide an important means of potable water in the event of a wilderness emergency. Nevertheless, under typical conditions makeshift solar stills rarely produce enough water for long-term survival, and the sweat expended in building one can easily exceed its daily output.’