Building #12- The Coal Tower Looking up the tallest structure left at ACME. Similar Images ...based on the tags: clouds, concrete, fire-escapes, numbers, signs, towers... 2005. Looking across the Mississippi from a park the night after the first snow. These machines had embossed metal numbers marking their ends. Originally, this part of the dock was reserved for the weather station. During the Cold War, the Air Force used the radar station to train bombardiers in radar-guided ordinance. From the bottom of the skyway I looked back, my eyes tracing the vines from the marsh up the smokestacks to the perfect Midwestern sky. Two signatures complement this gorgeous hand-painted sign. ‘Bowers’ from 1987 and ‘Normal’ from 1982. The blocking on the letters is still visible! On first impression it might look like a funky mailbox, but trust me on this one; it’s a flour bolter chute. In flour milling, “bolting” means sifting the flour through successively smaller screens. Frontier Gas is a former (?) gas station chain. Chain O’ mines reused a scrapped sign to mark their mill. Under the paint you can barely make out: GLORY HOLE GOLD MILL.