Visually, the most unusual of his designs was a small, heavy freight locomotive, the most powerful and last non-derivative design of 0-6-0 to operate in Britain. This Q1 class eliminated anything that might be considered unnecessary in locomotive design, including the traditional wheel splashers. With innovative lagging material that dictated the shape of the boiler cladding, the Q1 was regarded by many as one of the ugliest locomotives ever constructed. The 40 engines produced required the same amount of material needed for 38 more conventional machines, justifying the economies and design.