In either case, by simple mummification process ( not quite that simple but still occures in many different cultures spread through history around the earth ..besides Egyptian..
you can not preserve anything more or less than memory, also , biological memory , it's proved quite useful right now as they're able to read some of the DNA codes and it gives them certain amount of useful information ,
the movies about awakened mummies are fake of course . Ok, but what about stem cells and cloning ?
THE mummified body is a holistic pattern if you may , a trace . An imprint of Spirit , of the real Life form, to earthly bioshphere.
For the same reasons many other ancient cultures mummified their elders, Tibetan lamas or certain Brazilian tribes living in Amazon are just one example.
Thanks for posting the documentary link Olam, I will have a look and comment back later.
Just do not forget about 'evolution of human hypothesis'. The truth may not be fully known , may remain undisclosed openly in long time periods , it may be suppressed and cultural transposition of legend takes place that attempts to explain things the way they suit to some..
That's what is really happening, not recently, since very long time ago .
There's a lots of real-unreal transposition taking place in evolution of thought historically, in human society ..and it continues..one belief system evolves to another ..with help of your mind even, our mind ,
what is it to become yet no one knows for sure , it concerns not only faith and science , but global search for the big answers about mankind,
and till those are found, it's about believes.
'Egyptian belief system' is something once feeling as real as Christianity today , every belief system, even at its heights contains mystery.
What was not true that time can't be more true today but we try to discern what truth there was .
Sorry if I'm letting my tounge slip over cup of coffee
A