Gravity doesn’t suddenly increase its force on an object making it move the way it did in this video. If it were simply gravity, it would have just slid over, as things do often times. This isn’t a simple “gravity did it” answer when clearly there is more to this video than just that.
In subreddit r/Ghosts
In a post titled:
This is in my shop same 1850s building (below the rooms of the cat and winged ghost)