The Damp Machine

Went to visit a group of hippies camped at the edge of a forest.
They were showing me all their 'green' bits of equipment.
One was a artifact that kept things continually damp.
Not a great problem I thought as we squelched into the forest in a typical West Yorkshire downpour.
It turned out to be an upside down, pyramidal shaped, piece of foam around 6 feet in diameter. This was buried with its base flush with the forest floor.
Items requiring to be kept damp were secreted around its sides etc.
It was also camouflaged.
I had only been shown this as something important belonging to son C's mother was buried there.
It turned out to be a £20 note which C claimed as his own.
The note was falling to pieces and of doubtful value.
So, we dried it out and pasted it into a scrap book of other now useless items which had seemed important at the time.
A little record of our life.