Why did the Invisible Man feel insulted by Marvel’s refusal to accept his identity? What did he do to convince him?

Passing by the downs, the Invisible Man saw Marvel analyzing the worth of the shoes that he had got as charity. He intended to seek assistance from someone to procure the belongings that he had left behind. Marvel seemed to be an easy victim. The Invisible Man intervened by talking to Marvel who initially answered the voice without looking back. However, when he turned to see the person he had been talking to, he was confounded to find no one around. He thought to himself that perhaps his drunkenness was causing this hallucination. But the stranger still insisted his presence by violently shaking Marvel. Utterly dazed, Marvel decided to leave, he referred to the Invisible Man as ‘a blooming chump’, which was taken as a big insult by the Invisible Man. He found it difficult to accept that a insult by the Invisible Man. He found it difficult to accept that a good-for –nothing tramp like Marvel could have the insolence to ignore him.

Now he decided to convince Marvel into believing his presence. He started throwing stones at him. He hit Marvel’s foot causing him a lot of pain. The poor man ran for his life but tripped over something invisible. Threatened with yet another stone-hit, Marvel gave in and accepted that the Invisible Man actullaly existed.