Hi there. I have a quick query and I hope someone can help me. At present I am attempting to mark out the barrage lines for the 5th Australian Division's Left Group Artillery in March 1917. I am using the 1/10000 Map of Guedecourt to Thilloy and Beaulencourt dated 5/1/1917. I have come across the map reference N9C 55.10. Is the last number a Ten or a One? I am a bit puzzled by this. The barrage line reference is: N 22a 50.55-N15b8.3-N9c 55.10. All the best-Andy RUSSELL