Postmarked 1957; "Open house on the world's largest self-unloading limestone carrier during Detroit's Riverama days. Flagship of a fleet of seven giant self-unloader vessels of the Bradley Transportation Line of Michigan Limestone Division of U. S. Steel Corporation. Is engaged in the job of hauling millions of tons of limestone to steel mills, cement and chemical plants of lower lakes ports. Riverama emphasizes the importance of the Detroit River industrially and as a recreation facility."; addressed to Mr. and Mrs. Lee Mickle.