You still think like slaves, though we gained our freedom near four hundred years ago. But I have a vision for the Aachim. If the Clans are to go to the new world I must lead.

Come, said Luxor, urging them away. Not in front…

The image disappeared. Tiaan heard them talking but she could not make out what they were saying. After some minutes the image came back.

It is agreed, said Tirior. You will lead us, Vithis. Clan Inthis may take the honour of first across, if the gate succeeds.

You’d like us to take the risk, sneered Vithis. Then if something goes wrong, you’re rid of us! You’ve always resented Clan Inthis, Tirior.

Don’t be absurd, she replied.

I will be in the vanguard. I am prepared to take the risk for myself, as long as I see my clan safe. Clan Inthis will come last.

As you wish, she said equally coldly.

The risk is slight, said Luxor, since the device is unlikely to work. How could an untrained human possibly assemble a working zyxibule, even with an amplimet? Even at the greatest of all nodes? She will surely fail.

People do surprise, said Tirior, and this human has done it over and again. But, if there is to be a chance, she must have the best preparation we can give her. Let us not waste time. Minis, continue the instruction as we have laid it out for you.

‘I don’t understand what you’re trying to do,’ said Tiaan. They assumed too much.

Do you not? Minis sounded amazed. But you spoke of it months ago, back in the ice sphere.

‘I have no idea what you’re talking about,’ she said.

You asked the original question!

‘What question?’

You said, ‘What if I tear open the wall between Santhenar and the hyperplane?’ We assumed you knew. If it’s done just right, you can create a wormhole that way.

Tiaan was beginning to feel really stupid. ‘A wormhole?’

A passage that crosses a higher dimension between my world and yours. The hyperplane! You must have heard of gates, surely?

‘Well, of course I’ve heard of gates!’ she said. ‘They’re in the Histories. Why didn’t you say that in the first place?’

We assumed… Perhaps we assumed too much, said Minis. You seemed so knowledgeable. Never mind. Yes, we hope you can help us make a device to form a gate between your world and ours. We will, of course, control it from here. Listen carefully.

He explained a complicated set of test procedures and the responses required. When you have assembled the device, which we call a zyxibule, tested it according to our instructions, and all is working properly – AND NOT BEFORE, AT THE RISK OF YOUR LIFE – put your amplimet in the cavity at the centre and call again. Do you understand what I have told you?

‘I think so.’ She asked enough questions to be quite sure. ‘What will happen then?’

With luck, and if you can still contact me, and everything works perfectly after all this time, and the worlds are aligned, and you can channel enough power through the amplimet into the zyxibule, it will open a gate between Santhenar and Aachan and we will come through to our new world.

‘Are there many of you?’

Some thousands…

Tiaan was relieved. Enough to help with the war but not so many as to cause problems.

We are prepared. A few lyrinx will not trouble us. Will you get ready now?

‘I will.’ She feasted on Minis for a few seconds more. Soon he would be here and they would be together, forever! ‘But, Minis, what if I can’t channel enough power, or something else goes wrong?’

He looked uncomfortable. It could be that the gate won’t open. Or it might open but close again before we can come through… He trailed off.

‘What else?’ said Tiaan. ‘There is something else, isn’t there?’

Minis looked away, then was thrust aside and the hard face of Vithis appeared. You know the risk of using the amplimet, artisan. It could happen that in channelling so much power you will be burnt from the inside out, or your mind destroyed but your body living on. The risk of that happening is considerable. Perhaps one in three or four.

‘Oh!’ she whispered, sinking to her knees on the hard floor.

Another possibility is an explosion so colossal that the whole peak of Tirthrax mountain will be blown apart, and everything destroyed for twenty leagues around. We don’t know, artisan. We never thought this plan would work. There was not enough time to properly design the zyxibule. We think we know how it will work but we can’t be sure until we try it. Then, if it goes wrong, it will be too late.

Well? he snapped. Are you still prepared to do this, to save what is left of the Aachim species? Do you have the courage? Do not raise our hopes falsely.

What about my hopes? she thought desperately. Do I not matter? Clearly not to this bitter man. As an artisan, Tiaan had always lived with the threat of anthracism, though it had never happened in her manufactory. But this was an entirely different risk. She would have given up, but for Minis. Her death would be quick; his slow, painful and inevitable.

‘I will do it,’ she said in an almost inaudible voice, ‘if you will just explain again what I must do.’

Vithis did so, for Minis had not come back. Remember, when you have tested the device and put the crystal inside, call us. Be swift! the hard man said, and faded away.

FIFTY-SEVEN

The room guarded by three sentinels took a deal of finding, for so far they had seen only a tiny part of the vastness of Tirthrax. Halls and chambers stretched in all directions, carved into the heart of the mountain, and there were countless other levels, above and below.

It was Haani who found the room, for she spent her time wandering the halls. There were a number of chambers guarded by triple sentinels, though only one had the swirling symbol on the door, like an image of infinity.

As Tiaan touched her crystal to it, a representation of the lock sprang into her mind. It was like no other lock she had ever encountered. How did it work? She imagined the orbital chambers revolving. At once the mechanism went shuss and the door opened to her touch. Tiaan went in with Haani trotting at her heels. The room was crammed with machines and devices great and small, though what function they performed no amount of examination could tell her.

One was enclosed in glass, like a bell jar the diameter of one of the roof pillars outside. Within sat a spongiform object of rough ceramic, rather like the fire bricks that lined the furnaces of the manufactory. From the myriad little holes protruded wire filaments or fine glass tubes, or sometimes both, the former inside the latter. The object was mounted on a rough-sawn slab of basalt with swirling patterns in copper fused to its polished top. A bundle of glass tubes came from a socket in the base. Some had threads of wire inside, not connected to anything.

Another was a single hexagonal prism of a dark-green mineral, striated down the sides, floating in a sealed glass dish of quicksilver. The crystal looked to be tourmaline, though more perfect than any Tiaan had ever seen. It would have filled a bucket.

There were many and various metal objects, some rough castings, others polished to the most brilliant lustre. Several objects had crystals or shaped pieces of smooth ceramic inset, or attached to protrusions, or connected by cables, wires or threads.

There were devices driven by a variety of mechanisms, some clockwork, though few of the cogs seemed to have a regular number of teeth and not all the gears were circular. Others had gears meshing with threaded rods, wheels driven by belts, or wound with wires, or mechanisms whose action was not apparent no matter how carefully Tiaan inspected them. In others, the workings were hidden inside cubes of crystal or onion layers of tinted glass.