The Angels of Mons by Arthur Machen

It was during the Retreat of the Eighty Thousand, and the authority of the Censorship is sufficient excuse for not being more explicit. But it was on the most awful day of that awful time, on the day when ruin and disaster came so near that their shadow fell over London far away; and, without any certain news, the hearts of men failed within them and grew faint; as if the agony of the army in the battlefield had entered into their souls.

On this dreadful day, then, when three hundred thousand men in arms with all their artillery swelled like a flood against the little English company, there was one point above all other points in our battle line that was for a time in awful danger, not merely of defeat, but of utter annihilation. With the permission of the Censorship and of the military expert, this corner may, perhaps, be described as a salient, and if this angle were crushed and broken, then the English force as a whole would be shattered, the Allied left would be turned, and Sedan would inevitably follow.