( OK, I posted this as guest and thought I was logged in for my first post- delete the other one! )
'H' , I think, is the title of the sf short story but I cannot find it; maybe title is wrong: story involves a future soldier who is at front in mountains and all are firing blindly over a pass.
Then he gets leave, so he takes a train down into the valleys and time seems to dilate. When he returns to the front, all returns to the same and it turns out the "enemy" is probably themselves and what they launch over the rige is mirrored back at them.
I think at the front his name is "H" and it lengthens as he decends to valleys and shrinks to "H" when he goes back up.
Published in a 70s anthology, possibly 'Smoe and the Implicit Clay' was in same original collection.
What the heck IS this story and which book was it in??
For my first post here I'd like to solve this huge mystery.