Railroad Watch Auctions

I read this poem about a year ago and had two boys put a man on a false set of rail tracks and watch while a train has run over. They were thinking about having a good laugh at the reaction of the conductor, but when the man who operated the train was terrified at the thought that he had just killed a man, then realized it was a dummy and fell to the ground crying, the children could only sit and watch from their place nascondentesi and a boy puts his cosegna his ears to block out the agony of the conductor. Dearly love to know the name and the author of this work, because it was amazingly good writing.