I had 3 drums of ready-mixed with water cement. I was to let it stand in the drums overnight, then use it. We had a cannon in our yard. Ann drove my car and it tipped front end up. She got frightened and climbed out of it. I was riding a freight and it went over a safety switch which wrecks cars. It seemed to go off the truck. I yelled at the other brakeman to signal a stop. He did and it stopped.