Murray also patented an automatic damper that controlled the furnace draft depending on the boiler pressure, and he designed a mechanical hopper that automatically fed fuel to the firebox. Murray was the first to adopt the placing of the piston in a horizontal position in the steam engine. He expected very high standards of workmanship from his employees, and the result was that Fenton, Murray and Wood produced machinery of a very high precision. He designed a special planing machine for planing the faces of the slide valves. Apparently this machine was kept in a locked room, to which only certain employees were allowed access.