On the loaded Consett hoppers heading up to Medomsley, she would be banked all the way up to there and due to the switchback nature of the line would be coupled to the brake van, but provided with a slip coupling so the banker could be released without stopping. Stall Flatts signal box is visible in the distance. This dramatic view has one of Tyne Dock's ten Standard Class Nines darkening the sky as she climbs the demanding gradient up to Consett , most certainly with banking assistance at the rear of her train over this section of the track . The view also shows well the 56 ton Hopper Wagons with their side mounted and air operated discharge doors under control of the locomotive driver , together with their loads of iron ore , imported from abroad into Tyne Dock and now destined for the foundry at Consett some twenty six miles and a thousand feet above the docks . When the iron ore foundry was built high up at Consett in 1830 it used locally sourced deposits but as they dried up with the passage of time continued production relied upon imported ore of differing grades from many sources abroad , all of which came via Tyne Dock and this essential line .