A string of freight cars on the DSS&A is backing to the rail ferry dock in St. Ignace, Michigan. They will be loaded aboard the SS CHIEF WAWATAM and carried across the Straits of Mackinac to Mackinaw City where they will be sent south via the New York Central and Pennsy. You can see an air hose running up to the trainman who is blowing a shrill whistle to alert pedestrians and motorsts of the backing train.