House of Leaves:things disappearing in the hallway

I found it interesting how much things change while the characters are in the hallway. For example on page 285 I found that within just a few pages that the rope goes from being there to vanishing within seconds. The fact that within this hallway that when a person just forgets about the rope that he is holding it suddenly vanishes. I also found it unusual that even though the rope disappeared that was holding Reston,Reston is still moving and still attached to the rope. This part of the text I thought was very unusual and interesting that things disappear but also are not totally gone at the same time.