I am not sure I like this Frank Gresham. I let ride him calling Mr Moffatt a muff for saying he would vote to let Jews stand for parliament. SPOILER However the violent act he commits on Mr Moffatt: I am surprised it could be considered tolerable even then. I remember reading in The Tenant of Wildfell Hall one of the gentlemen protagonists committed a very violent act, and thinking that was very shocking. However, I felt that was more acceptable than Frank Gresham's behaviour, as it was not premeditated, he was being needled by the person he assaulted, who he had warned and who knew he was already upset. OTOH, Frank Gresham would be prosecuted for Grievous Bodily Harm with Intent if he did what he did today. What makes it worse is that it was premeditated and that he conspired with a friend to make it happen.
I have a bit of a temper that has got me into scrapes, but nothing like this. Sorry Frank, I think you're a cad, and I would black ball you if you applied to join my gentleman's club.