Cryptonomicon

He finds his way round the mansion to the narrow lane that runs between it and its row of red-brick garages (or stables, as his grandparents would be likely to peg them). He finds it a very pleasant place for a cigarette. The lane is lined with trees, a densely planted hedge of them. The sun is just setting now. It is still high enough to snipe through any small defects that it finds in the defensive perimeter of the horizon, so narrow red beams strike him surprisingly in the eye as he ambles back and forth. He knows one is shining invisibly through the clear air several feet above him, because it is betraying an aerial: a strand of copper wire stretched from the wall of the mansion to a nearby cypress. It catches the light in precisely the same way as the strand of the spiderweb that Waterhouse was playing with earlier.

The sun will be down soon; it is already down in Berlin, as in most of the hellish empire that Hitler has built from Calais to the Volga. Time for the radio operators to begin their work. Radio does not, in general, go around corners. This can be a real pain when you are conquering the world, which is inconveniently round, placing all of your most active military units over the horizon. But if you use shortwave, then you can bounce the information off the ionosphere. This works a good deal better when the sun is not in the sky, sluicing the atmosphere with wideband noise. So radio telegraphers, and the people who eavesdrop on them (what the Brits call the YService) are, alike, nocturnal beings.

As Waterhouse has just observed, the mansion has an aerial or two. But Bletchley Park is a huge and ravenous spider that requires a web the size of a nation to feed it. He has seen enough evidence, from the black cables climbing the mansion's walls and the smell and hiss of the massed teletypes, to know that the web is at least partly made of copper wires. Another piece of the web is made of rude stuff like concrete and asphalt.

The gate swings open and a man on a green motorcycle banks steeply into the lane, the two cylinders of his machine blatting away, the noise stinging Waterhouse's nose as he rides by. Waterhouse strides after him for some distance, but loses his trail after a hundred yards or so. That is acceptable; more of them will be along soon, as the Wehrmacht's nervous system awakens and its signals are picked up by the Y Service.

The motorcyclist went through a quaint little gate that joins two old buildings. The gate is topped by a tiny cupola with a weathervane and a clock. Waterhouse goes through it and finds himself in a little square that evidently dates back to when Bletchley Park was a precious Buckinghamshire farmstead. To the left, the line of stables continues. Small gables have been set into the roof, which is stained with bird shit. The building is quivering with pigeons. Directly in front of him is a nice little red brick Tudor farmhouse, the only thing he has seen so far that is not architecturally offensive. Off to his right is a one-story building. Strange information is coming out of this building: the hot-oil smell of teletypes, but no typing noises, just a high mechanical whine.

A door opens on the stable building and a man emerges carrying a large but evidently lightweight box with a handle on the top. Cooing noises come from the box and Waterhouse realizes that it contains pigeons. Those birds living up in the gables are not feral; they are homing pigeons. Carriers of information, strands of Bletchley Park's web.

He homes in on the building that smells of hot oil and gazes into a window. As evening falls, light has begun to leak out of it, betraying information to black German reconnaissance planes, so a porter is strutting about the courtyard slamming the black shutters closed.

Some information comes into Waterhouse's eyes at least: on the other side of that window, men are gathered around a machine. Most of them are wearing civilian clothes, and they have been too busy, for too long, to trifle much with combs and razors and shoe polish. The men are intensely focused upon their work, which all has to do with this large machine. The machine consists of a large framework of square steel tubing, like a bedstead set up on one end. Metal drums with the diameter of dinner plates, an inch or so thick, are mounted at several locations on this framework. Paper tape has been threaded in a bewilderingly loopy trajectory from drum to drum. It looks as if a dozen yards of tape are required to thread the machine.

One of the men has been working on a rubber drive belt that goes around one of the drums. He steps back from it and makes a gesture with his hand. Another man flips a switch and the drums all begin to spin at once. The tape begins to fly through the system. Holes punched in the tape carry data; it all blurs into a grey streak now, the speed creating an illusion in which the tape appears to dissolve into a ribbon of smoke.