An accidental old man

A very old man fell down a hole when he was out
walking looking at the pattern of the clouds.
The earth was loose when he tried to climb up, kept
sliding down, so he sat waiting, and it was evening.
He fell asleep and during the night water from
an ancient sea rose and filled the hole so he could
float holding onto a root, and when the water was
level with the ground he could get up and get out.
The sea that had been trapped so long kept rising
and the valley became a lake and his house which
had been on the high ground a sought-after property,
and he could afford to buy a coffin of mahogany  
with brass handles.