Original oil and gas trade magazine vintage ad for THE OIL CONSERVATION ENGINEERING COMPANY. Main office and factory was located at Addison Road at N.Y.C. Tracks, Cleveland, OH. Warren City Tanks To be OCECO Equipt (Equipped). Warren City Tank & Boiler Company. Manufacturer of Gauge and Thief Hole Covers, Roof Manhole Covers and Vent Equipment. Unique 1924 old gasoline station storage equipment magazine advertisement. (Image scan shows a slight pink tint that is not part of the actual ad). Approximate size 9 x 12 inches.