Lorna paused, taking a breather after the climb up the cliff, thinking that Bradd would soon catch her up.
The windows of the institute building were lit from within, but every pane of glass was curtained so that it was impossible to see inside. Lorna knew that at this time some of the cartographers would still be bent over their drawing tablets and terminals, but most would have stopped work for the night. Some of them would have stayed behind to use the bar, but a lot of the staff simply went home at the end of the day. Lorna and her friend Patta were unusual in renting one of the institute’s small service flats inside the main building.
Beyond the Institute, the town, the inland heights of Meequa’s range of hills. Sometimes, people who worked in the Institute went on hill-walks up there in the heights, but because of the friable nature of the rocks the hills were not safe for climbing or exploring. Lorna herself had never been far inland from the coast. She preferred to leave the dark peaks a private mystery in the background of her life, an unexplored enigma.
The hills held other more tangible riddles too: Meequa was an important part of the network of military installations and bases found all over this sector of the Archipelago. Large areas of the hill country were forbidden to the public, even to members of the MCI staff, who were nominal collaborators in the drone project. Somewhere beyond the first range of peaks behind the town was the base to which the drones returned, where they landed, somewhere dark, unlit, controlled by computer robots, collecting and storing data, information that was more than just the mapped details that were passed on to the institute: military intelligence, mining data, probable oil reserves, weapons caches, sources of energy. None of that disagreeable practicality was any part of Lorna’s own enigma. She sensed a deeper, more personal absence because of her loss of Tomak.
Tomak’s disappearance was probably explained by the hidden interior of this island, rather than by the uncharted highlands of the other. But Meequa was for her an island like a thousand others in the Archipelago, harbouring a seashore mentality, a littoral culture, turning its back on the engine of military intention and strategy that powered the island economies from inland, looking instead outwards to the unmapped seas, carelessly idle in the warmth, languorous under the sun, dreaming in the days.
The drones went out again before dawn, whispering above the roofs of the town, heading out across the sea. By the time Lorna was awake they had all disappeared, but another swarm of drones sent out earlier would be returning in the evening. The drone journeys were long: the solar-powered batteries could keep the flimsy craft flying for days or weeks. Many never returned. Some were shot down by troops: the enemy, of course, but even friendly gunners were known to use the drones for target practice if they strayed too near a base or a fort. Others crashed when the software failed and they collided with each other or with something on the ground, while more ran out of energy when they strayed too far south or north, and became trapped in a night that was too long for their batteries to be revived by the coming of sunrise.
But there were others, and these were the ones that Lorna loved to dream about. People from all over the Archipelago told stories of drones that became trapped in their own software. They somehow wandered into an area of terrain, a range of hills, a stack of rocks, a pattern of islands that set up radar avoidance patterns in the directional controls, but also closed a loop from which the drone could never escape.
Lorna had heard of more than thirty islands which had acquired attendant drones, constantly touring or circling the mountain heights, or zooming along the seashore, or heading bravely out to sea only to be returned by the detected barrier of a neighbouring island. One pair of islands in the Aubrac Chain had fortuitously created a virtual figure-of-eight, around which the captured drone constantly flew, never escaping, day after day, night after night.
Sometimes Lorna imagined that if the mapping enterprise went on long enough, every island would eventually have its own drone, permanently circling with its flow of silent, silvered wings.
When she arrived in the office that morning she downloaded a fresh set of drone images for the general area of the Swirl — the date identifying them was nearly two and a half years earlier.
She began as usual with the preliminary scanning, which filtered out and discarded approximately ninety-five per cent of everything: these were the unworkable, unusable images of the surface of the open sea, or of unidentifiable patches of land, or were blurred by motion or simply out of focus.
The secondary level of search on the remainder involved the fragments that might be identifiable in some way, and therefore able to be matched with previously stored images: these were usually glimpses of shallower seas, lengths of reef, concentrations of fish, large isolated rocks, or on land surfaces they might be clear images of mountains, or part of a river, or dwellings, or even short stretches of coastline. There were scanning and matching programs which could handle these, so she transferred the images to the computer and left it to sort out what it could. Occasionally, once every few weeks, one of the computers would report a matching image, causing amused relief and ironic cheers from the staff.
The material that was left after all this filtering was for her to search manually. These were the coherent images, the ones that promised to be identifiable. This was the real work for her, where all her time went. Using complex imaging software on her terminal she tried to match and compare the main images.
This morning the most promising result had been produced by a series of fifteen contiguous drone shots. These readily connected into an unbroken stretch of rocky shoreline, for which the computer reported more than a hundred and fifty possible matches with existing downloads. Lorna had to look at each of these herself, trying to match them against the new image. In this particular case, the problem was that many of the rocks appeared to be volcanic in source, which might mean that they had been ejected comparatively recently and therefore would not match with anything. The software made corrections for height, angle and colour variations, but even so the final decision was almost always hers, or one of the other cartographers’.
Then again, the shore might be part of one of the hundreds of Swirl islands she had not so far identified. Even beyond that, it was not unknown for the drone search pattern to be identified or labelled in error. Many hours of wasted search time were regularly lost on searches for the wrong island in the wrong part of the ocean.
The day passed with normal absorption into this routine work: she took a long break at midday and went for a walk with Patta, and towards the end of the afternoon put away the search work and caught up with some correspondence. Various universities were funding the Institute’s cartographic project, and there was a constant traffic of information to and from research departments in every part of the world. All the cartographers in Lorna’s section had to take on some of this daily work.
She was about to close down her desk for the day when her terminal quietly emitted an incoming-data warning and a large file began to arrive.
It was a detailed graphic, loading slowly. The time estimate was two minutes for completion. Lorna’s first reaction was to leave it and examine it properly the next day. It was early evening and she was planning to walk down to the beach as she so often did, to watch the returning drones. As she looked at the screen, though, she suddenly realized what the graphic consisted of, or at least what the title at the top claimed it to be.
It was a highly detailed map of the island of Tremm. It was topographically exact with 3-D representations of the physical features, all towns and settlements shown, as well as roads and unidentified ‘installations’, which Lorna realized at once were probably the military bases. There was even meticulous nautical representation, showing all the offshore sea depths, position of reefs, navigable channels, and so on.