Why did hundreds of people send canes to preston brooks?

Preston Brooks was a Southern Congressman and a passionate advocate of Southern Rights. Charles Sumner was an ardent abolitionist who delivered an impassioned speech against the authors of the Kansas-Nebraska Act of 1856. He also ridiculed the speech impediment of one of the authors, Andrew Butler. Preston Brooks got angry because he was the nephew of Andrew Butler. Together with a friend, Brooks approached Sumner as the latter worked at his desk and started caning Sumner. Sumner collapsed in the aisle and Preston Brooks continued caning him until his cane broke. Southerners sent canes to Preston Brooks to replace the one he broke.