Hello all. I hope someone can assist with WWI period Highland Railway and North British Railway livery information as well as a couple of other questions. I have been contacted by an American gentleman, John Bower, who wrote: "I am doing research into my grandfather's World War One US Navy service in Scotland with the North Sea Mine Barrage. His pictures of equipment show wagons with M and M with an upward arrow between. Can I assume this was a 1918 livery for Ministry of Munitions? May I send