 In the former case, the valve cylinder was mounted directly inboard from the high-pressure cylinder; in the latter case, the valves were also placed inboard, but at a level between the two power cylinders.The placement of the valves necessitated an inside-connected valve gear, and the Stephenson pattern was used (being the dominant type of the era anyway).One extra appliance required was a starting valve, manually controlled, which allowed admission of high-pressure boiler steam directly to the low-pressure intake.