Radio

Radio is how the spiders speak across distance, and the only channel between their world and the Messenger in orbit. They call the medium the invisible web, or the strands of the ether.

Description

Silk carries simple speech along short strands that run everywhere in a spider city. Radio reaches further, and the temple in Great Nest keeps a rigorous monopoly on the invisible traces of radio waves.

The first instrument was a crystal receiver. Generations of work turned it into a machine of metal, wood and silk, so that a priestess can speak with other temples across half the world and with the Messenger itself.

Even Portia’s radio is biological. When the ark ship’s crew set off an improvised electromagnetic pulse, the spiders felt a strange wind in airless space and radio contact went patchy for a while. What the pulse touched was already regrowing, with replacements growing behind working components like shark’s teeth.

Another device used in the war is a bulky glass instrument bound in silk. It holds a colony of ants that makes a compound view of what lies in front of it and relays the picture to the orbital web and the planet.

First contact

For an unknown stretch of time the Messenger sent a radio signal made of mathematical sequences. Answering it took more than Bianca’s battery, which on its own would not make a transmitter, and the work on casting an electromagnetic voice into the ether went on for years.

The first message sent was We are here. Within a second of the last solution going out, the Messenger stopped its own transmissions, and the civilisation panicked at the thought that it had offended the universe. Several fraught days later the Messenger spoke again.

A frequency each

Every temple is assigned its own frequency, and the message is substantially the same for all of them. That did not stop Great Nest from treating its knot of frequencies as a resource. Portia eavesdropped on the dictates to other nests, and pilgrims came begging for word of what the Messenger wanted. The radio also carried news of how far other temples let heretics speak before they acted.

Pictures

Bianca’s advance was to send a picture. A colleague had bred a colony of seeing ants, and the colony’s view was encoded as a spiral of dark and light dots. The Messenger understood that an image had arrived but not how to read it, until Bianca sent formulae describing the spiral. God then proved to have a word for airship.

The exchange led her to a conclusion of her own. The Messenger cannot see the world beneath it. It is blind, and radio is its only means of sight.

Bianca could have kept talking past the horizon by passing her signal hand to hand between transmitters, though she waited for the Messenger to come round again.

Up to orbit

The Star Nest carried a transmitter and receiver in its cramped cabin, and its crew sent regular reports to Viola and to the wider world. Viola had radio beacons on the ground to steer by, and dozens of observatories and receivers waited below for news. The transmitter struggled to reach the surface at that height, so Fabian’s report of the failed release came out in repeats until, alone in the falling ship, he asked whether anybody could receive him. The Messenger answered.

The payload of that flight was a radio relay: a glass ball with two hulls, a transmitter and receiver, and two colonies inside, one of ants and one of algae, to keep it running for a year.

War between the cities

Great Nest’s transmitters struck first, with an ultimatum to its weaker neighbours. The day after the first battle, a simple radio message reached Seven Trees and its allies: Now we will come for you.

The war from orbit

By the time the Gilgamesh came back, a compact radio was part of a spider’s orbital kit, carried against the abdomen. Out beyond the planet, biotechnological receptors in the cold of space listened for radio messages and for anything else moving in the electromagnetic spectrum.

The ark ship’s crew jammed it. A wash of white noise swallowed the radio, and Portia’s squad was cut off along with every other squad on the hull. She searched for clear frequencies, guessing that the giants kept some channels open for their own speech, and with the radio gone she gave her orders by tapping on the hull and flashing her palps.

Unanswered questions

• Who built the first crystal receiver, and how long it took the temples to make it speak both ways.
• Whether the relay satellite stayed in its orbit or fell, as its makers expected, within a year.