In paragraph five, how does Kafka transform Gregor's thoughts about his boss into images?

Kafka's ise of imagery portrays Gregor's boss as a superior man, who looks down on his employees. He isn't someone you challenge, and if anyone had the nerve to stand up to him, it would completely shock him.

If I didn't have my parents to think about I'd have given in my notice a long time ago, I'd have gone up to the boss and told him just what I think, tell him everything I would, let him know just what I feel. He'd fall right off his desk! And it's a funny sort of business to be sitting up there at your desk, talking down at your subordinates from up there, especially when you have to go right up close because the boss is hard of hearing.