‘There may be a couple of dozen of them. Of course the distribution may not be a simple spacing with distance, or latitude. We’ve no way of knowing, without a view from orbit.’
‘This is just as you anticipated, it seems, Lobsang. Global. I wonder how long it took them to build all this.’
‘We’ve no meaningful way to answer that question, Joshua. We don’t know how long they’ve been here, on this world. Or how fast they work. I suspect they’ve accelerated their progress since they encountered us. Getting it done before we can react. But that’s only a guess, for now.’
‘OK. But why, Lobsang? What’s it all for? A transport system? Rail lines? Are these aqueducts, like the Romans used to build?’
‘I doubt it’s anything so simple. I could make guesses, but it would not be constructive at this stage.’
Joshua studied him. His face, underlit by the tablets’ glow, was even harder to read than usual. ‘You sound subdued. Are even you in awe of what these beetles are building?’
There was no reply.
‘So, what next?’
Lobsang said thoughtfully, ‘We’ve come under no threat. The beetles must be aware of our movements; we passed over a work party, remember, on the New York viaduct. We are evidently irrelevant to them. And our findings cannot be lost, even if we do not return; I have already sent short-wave radio reports back to Agnes.’
‘You think we should go on. All the way to the equator?’
‘That’s what I suggest.’
‘Then let’s do it.’
The airship forged on, tracking the North American east coast, heading steadily south.
It was evening of this third day of the journey when they came upon the next viaduct, another five hundred miles or so south. This one spanned Florida, at about the latitude of Miami.
They reached the next viaduct south, another five hundred miles or so, about midday of the next day. It cut across the ocean itself with no land in sight, to north or south. Under a cloudy noon sky, the viaduct was difficult to make out against the grey shoulder of the ocean.
‘There’s no Mexico here,’ Joshua said, checking their position on a tablet map.
‘Very observant.’ Lobsang told Joshua that on this world – and on similar worlds in this band – Mesoamerica did not exist, as they knew it from the Datum. ‘Here, the Pacific breaks through into the Gulf of Mexico. And if you were to cross the Atlantic you’d find the Mediterranean flowing through the Middle East into the Arabian Sea. So there is a continuous waterway running all the way around the planet, at about this latitude. As a result the global ocean currents are different. Once, long ago, it was like this on the Datum; the palaeontologists call it the Tethys Sea. In fact some Long Earth geographers call these worlds the Tethys Belt.’
‘I guess that’s one reason the world’s warmer?’
‘Yes. And if they’ve straddled the whole world with a viaduct at this latitude, the beetles must have mostly encountered ocean, on their way around. An incredible feat of engineering.’
Joshua said, ‘And I used to think oil rigs out on the Gulf were impressive.’
‘Onwards, Joshua?’
‘Onwards, Lobsang.’
They came upon the next viaduct at dawn of the next day, the fifth of the journey. It clipped the northern coast of Venezuela – the northern shore of South America, which was, in this world, an island continent separate from the north.
They continued south, leaving the viaduct behind, crossing dense jungle, a green chaos beneath them.
Lobsang said, ‘That forest is probably full of exotic animals of kinds nobody ever encountered before. An island world.’
‘Leave it for your grandchildren to explore, Lobsang.’
On they sailed, heading deeper over the interior of the continent now, riding through another day and into the night. And at about midnight they came to yet another viaduct. This was the equator. Lobsang recommended they wait out the night to see it properly.
They came together at the windows at about six a.m., on the sixth day of their journey.
The airship drifted in the air directly over the viaduct. It ran, Joshua saw, almost parallel to the course of a tremendous river.
‘That must be the local Amazon,’ he said.
‘Yes.’
‘So now what? Do we descend? Down I’ll go with an electronic parrot on my shoulder, just like old times?’
Lobsang forced a smile. ‘We don’t want to provoke any hostility. For now we wait.’
‘For what?’
‘Again, I suspect that when it comes, we won’t be able to miss it.’ He yawned and stretched, quite convincingly. ‘Now might be a good time to make breakfast, Joshua. Anything but chowder …’
‘Fair enough.’ Joshua rummaged through the tiny galley. They had frozen meat and French fries, and energy to spare; he decided to make burgers. As he got to work he said, ‘You know, I said it before, we’re going to have to do this properly.’