Harry James Malony et al - French-English Dictionary of Machine Gun Terms (1918)
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I'll admit the only reason for this post is that title, which inexplicably made me laugh. (Which I later realized could sound like a dig at the French but they've been some of history's toughest soldiers for centuries so no.) Clearly an important topic at the time (for certain people anyway) but not so much today. Some illustrations would have been nice.