News From a Distant Planet:

Historians on the distant planet have unearthed
a tome regarding the burial rituals of the previous
inhabitants. When one would die, the head would be
removed and placed in an airtight jar. The jar would
then be weighted and taken far out on the ocean.
The encased head would be dropped and left behind.
It had been believed that the sea and air composed the
spirit bodies of the recent dead. The head was needed
for the brain possessed the spirit's power.