Jerry carefully examined the room and in one corner he discovered the same marks, with the walls on both sides exhibiting a faded area. He then proceeded to the adjacent room to determine the size of this area on the wall.
This was a likely confirmation that some kind of supernatural phenomenon had originated from Dave's side, passing directly through the wall and exiting through this corner.
"Brother, what's behind the wall I'm facing?" Jimmy pointed to his current position.
Prison guard: "Behind that are the clean water pipes, sewage pipes, and the steam heating ducts. Further out, you reach the building's wall."
Jimmy: "Is there a map?"
Prison guard: "There's one in the office."
Jimmy: "Is there a tape measure in the office?"
Prison guard: "Yes, there is."
