Analysis of Behind The Hill (The Adventures Of Seumas Beg)

Behind the hill I met a man in green
Who asked me if my mother had gone out?
I said she had.    He asked me had I seen
His castle where the people sing and shout
From dawn to dark, and told me that he had
A crock of gold inside a hollow tree,
And I could have it., I wanted money bad
To buy a sword with, and I thought that he
Would keep his solemn word; so, off we went.
He said he had a pound hid in the crock,
And owned the castle too, and paid no rent
To any one, and that you had to knock
Five hundred times.    I asked, "Who reckoned up?"
And he said, "You insulting little pup!"