why does vardaman hit peabody's horses so they break loose and run away with the buggy?

he realizes that he killed and cut up the fish and assumes that someone must have killed his mother. Since she died after Peabody came, he blames Peabody. He rushes to the barn to get a stick, possibly intending to hit Peabody Vardaman doesn't hit Peabody. Instead, he strikes Peabody's horses, who race off pulling the buggy.