Well, because I'm not the one who asked the question "So in what year exactly was it that it was no longer considered proper to beat your political opponent on the floor of the House of Representatives?"
You might just learn that Scumner was beaten on the floor of the Senate.
LOL! :)
Incidentally, here's what Wikipedia's entry about Brooks says
Long afterward Charles Sumner said that "It was slavery, not he, that struck the blow." In 1872, Sumner visited the Congressional Cemetery; when a friend pointed out a cenotaph of Brooks and asked Sumner how he felt about Brooks. Sumner said "Only as to a brick that should fall upon my head from a chimney. He was the unconscious agent of a malign power.