The Escapement by K. J. Parker Page A

palisades, cuvettes, cordons, scarp and counterscarp revetments, embrasures and escalades were, but he still couldn't get his poor head around counterforts or ecluses. It was the pictures, though, that haunted him. The shapes were just shapes; abstracts, symmetrical patterns of lines, essays in the geometry of violence, manmade and unnatural—except that they kept reminding him of things, and that was what was so disturbing. The bastion with complex ravelins assailed by saps and defended by countermines, for example, put him in mind of the head of an insect, with multiple eyes and projecting feelers, while other formations and patterns were stars or snowflakes, perfect but encumbered with strange and malevolent growths swelling out of them, grotesque and disgusting in a way that no picture of people or animals could ever be. At times, he caught himself feeling afraid of the book; savages and primitives believed in books that could suck your soul out through your eyes as you read them, books that could wrap their pages round your head and swallow you, words that crawled into your brain like tapeworms. Of course, he wasn't a primitive or a savage.
    Saps; they, he was beginning to understand, were the real danger. If everything in the Grand Over-Arching Schedule actually happened, the City would be safe from Vaatzes' stone-throwers (not for ever, but for long enough; query, however, whether time fences in a straight line or a circle); and all the enemy had to do in order to be safe from the City's engines was to fall back a hundred yards or so. Artillery, then, was a negatable threat, and once both sides had figured that out (he had a depressing feeling they wouldn't take his word for it and save themselves the effort), the war would go underground and start burrowing, like maggots.
    The book had plenty to say about sapping; about mines, countermines, camouflets, petards, galleries, stanchions and globes of compression. The basic idea was very simple: dig a tunnel under a wall. To keep it from caving in while you're building it, you need to hold up the roof with wooden props; when you've finished, you pack the end of the tunnel, directly under the foundations of the wall, with straw, brushwood and scrap lumber, all thoroughly soaked in lamp oil. Strike a spark and run; the fire burns through the props, down comes the roof, and the ensuing subsidence topples the wall.
    Try that with a solid bank of earth, of course, and you achieved very little—a few dimples, maybe a crater, but nothing you could send an army into and hope ever to see it again. The book was ruthlessly straightforward when it came to proposing a countermeasure: first, storm the bastion . That was the point at which Psellus closed the book. He wasn't quite sure why, or at least he couldn't reduce it to words, but it was something to do with the thought of the unspeakable degree of effort involved—
    first storm the bastion, then start digging tunnels, where necessary chipping through any solid rock that might be encountered in the process. The thought of it—the work, the slaughter, the sheer weight of dirt to be shovelled into baskets in the dark and carried—made him feel sick. He looked at the pictures and saw the heads of insects; he read about sapping, and thought about ants. It was all too inhuman. (Also, pointless; but it would have to be done, even though it wouldn't win the war. Only a letter could do that.)
    Well, there was still time. He could force himself to read the rest of the book later, when it became unavoidable. In the meantime, he submerged himself with an enthusiasm little short of joy in banal, tedious administration, like a fish thrown back into the water by an angler. His clerks glared at him behind his back, of course. They felt that his insistence on doing routine paperwork that should have been their job was intended as a criticism. He felt bad about that; but he needed the columns of figures to soak up the diagrams that lingered in