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This actually collects two different booklets, one on trench war and the other bayonets. One oddity is that judging by the author's appeal for distribution it's not an official training manual but something he published and then hoped to get into the army's hands. Still it seems to have sold fairly well and the library stamps on this scanned copy show it checked out several times even in the 1980s and 90s. Its real use today (other than preparing for the zombie apocalypse) is the detail on mechanics of tactics and construction generally overlooked in historical accounts.