 Complete the following phrase:  An incident involved Robert Todd Lincoln son of American president Abraham Lincoln and a platform gap in Jersey City, New Jersey during the American Civil War. While waiting on a crowded train platform, Robert Lincoln was pushed against the train, and the train started to move, dropping his feet into the gap. He was saved from possible serious injury or death by the prompt actions of well-known actor Edwin Booth the brother of John Wilkes Booth, who a few months later would 