What is the metaphor in again spector raised a cryand shook his chain and wrung shadowy hand?

In the line "again spector raised a cry/ and shook his chain and wrung shadowy hand", the metaphor is that the "spector" (a ghost or apparition) is representing a person or force that is causing fear or anxiety. The "chain" and "shadowy hand" are symbols of this fear or anxiety. The line is suggesting that this person or force is trying to break free from the chains that bind it, and is causing a great deal of distress in the process.