Why the last page: four corner apples and the words NOTES

This is an anagram of 'STONE' (easy for a child or an adult)

I firmly believe that this has been hidden under a large rock
or boulder. "I left the fallen brave by a large boulder,
knowing that many unseen eyes had watched me."

Reread the last four or five verse of the rhyme,
it describes the lifting of a large rock using a
lever system (first need to construct)

And the last mysterious phrases....

Lets discuss.