Stone Furnace. The back of the photograph is marked: "Iron was last smelted in the blast furnace at the Katahdin Iron Works near Brownville, Maine in 1890. The operation started in 1843 and at its peak produced 2,000 tons of iron yearly." The lower right hand corner of the photograph is singed.
LaRue Spiker, “Stone Furnace,” Mount Desert Island Historical Society, accessed May 14, 2024, https://mdihs.digitalarchive.us/items/show/9898.Item 10264
