Edipon’s eyes opened wider and wider while Jason talked until they stuck out of his head like boiled eggs. “Demon!” he screeched and tottered towards Jason with the knife extended. “You couldn’t have seen, not through stone walls, yet only my family have seen, no others — I’ll swear to that!”

“Keep cool, Edipon, I told you that we have been doing this stuff for years in my country.” He balanced on one foot, ready for a kick at the knife in case the old man’s nerves did not settle down. “I’m not out to steal your secrets, in fact they are pretty small potatoes where I come from since every farmer has a still for cooking up his own mash and saving on taxes. I’ll bet I can even put in some improvements for you, sight unseen. How do you monitor the temperature on your cooking brew? Do you have thermometers?”

“What are thermometers?” Edipon asked, forgetting the knife for the moment, drawn on by the joys of a technical discussion.

“That’s what I thought. I can see where your bootleg joyjuice is going to take a big jump in quality, if you have anyone here who can do some simple glassblowing. Though it might be easier to rig up a coiled bi-metallic strip. You’re trying to boil off your various fractions, and unless you keep an even and controlled temperature you are going to have a mixed brew. The thing you want for your engines are the most volatile fractions, the liquids that boil off first like gasoline and benzene. After that you raise the temperature and collect kerosene for your lamps and so forth right on down the line until you have a nice mass of tar left to pave your roads with. How does that sound to you?”

***

Edipon had forced himself into calmness, though a jumping muscle in his cheek betrayed his inner tension. “What you have described is the truth, though you were wrong on some small things. But I am not interested in your thermometer nor in improving our water-of-power, it has been good enough for my family for generations and it is good enough for me….”

“I bet you think that line is original?”

“… There is something that you might be able to do that would bring you rich rewards. We can be generous when needs be. You have seen our caroj and ridden on one, and seen me go into the shrine to intercede with the sacred powers to make us move. Can you tell me what power moves the caroj?”

“I hope this is the final exam, Edipon, because you are stretching my powers of extrapolation. Stripping away all the shrines and sacred powers I would say that you go into the engine room to do a piece of work with very little praying involved. There could be a number of ways of moving those barns, but let’s think of the simplest. This is top of the head now, so no penalties if I miss any of the fine points.

“Internal combustion is out, I doubt if you have the technology to handle it, plus the fact there was a lot to do about the water tank and it took you almost an hour to get under way. That sounds like you were getting up a head of steam — the safety valve! I forgot about that. So it is steam. You go in, lock the door of course, then open a couple of valves until the fuel drips into the firebox, then you light it. Maybe you have a pressure gauge, or maybe you just wait until the safety valve pops to tell you if you have a head of steam. Which can be dangerous since a sticking valve could blow the whole works right over the mountain.

“Once you have the steam you crack a valve to let it into the cylinders and get the thing moving. After that you just enjoy the trip, of course making sure the water is feeding to your boiler all right, that your pressure stays up, your fire is hot enough, all your bearings are lubricated and the rest….”

Jason looked on astounded as Edipon did a little jig around the room, holding his robe up above his bony knees. Bouncing with excitement he jabbed his knife into the table top and rushed over to Jason and grabbed him by the shoulders, shaking him until his chain rattled.

“Do you know what you have done?” he asked. “Do you know what you have said?”

“I know well enough. Does this mean that I have passed the exam? Was I right?”

“I don’t know if you are right or not. I have never seen the inside of one of the Appsalan devil-boxes.” He danced around the room again. “You know more about their… what do you call it, engine… than I do. I have only spent my life tending them and cursing the people of Appsala who keep the secret from us. But you will reveal it to us! We will build our own engines and if they want water-of-power they will have to pay dearly for it.”

“Would you mind being a little bit clearer,” Jason pleaded. “I have never heard anything so confused in my entire life.”

“I will show you, man from a far world, and you will reveal the Appsalan secrets to us. I see the dawn of a new day for Putl’ko arriving.” He opened the door and shouted for the guards, and for his son, Narsisi, who arrived as they were unlocking Jason who recognized him as the same droop-eyed and sleepy looking D’zertano who had been helping Edipon to drive their ungainly vehicle.

“Seize this chain my son and keep your club ready to kill this slave if he makes any attempt to escape. Otherwise do not harm him, for he is very valuable. Come.”

He tugged on the chain, but Jason only dug his heels in and did not move. They looked at him, astonished.

“Just a few things before we go. The man who is to bring the new day to Putl’ko is not a slave, let us get that straight before this operation goes any further. We’ll work out something with chains or guards so I can’t escape, but the slavery thing is out.”

“But — you are not one of us, therefore you must be a slave.”

“I’ve just added a third category to your social order. Employee. Though reluctant, I am still an employee, skilled labor, and I intend to be treated that way. Figure it out for yourself. Kill a slave and what do you lose? Very little if there is another slave in the pens that can push in the same place. But kill me and what do you get? Brains on your club — and they do you no good at all there.”

“Say, Dad, does he mean I can’t kill him?” Narsisi looked puzzled as well as sleepy.

“No, he doesn’t mean that. He means if we kill him there is no one else that can do the work he is to do for us. I can understand him and I do not like it. There are only slaves and slavers, anything else is against the natural order. But he has us trapped between satano and the sand-storm so we must allow him some freedoms. Bring the slave now… I mean the employee… and we will see if he can do the things he has promised. If he does not, I will have the pleasure of killing him because I do not like his revolutionary ideas.”

***

They marched single file to a locked and guarded building with immense doors, which were pulled open to reveal the massive forms of seven caroj.

“Look at them,” Edipon hissed and tugged at his nose. “The finest and most beautiful of constructions, striking fear into our enemies’ hearts, carrying us fleetly across the sands, bearing on their backs immense loads and only three of the things are able to move.”

“Engine trouble?” Jason asked lightly.

Edipon grumbled, cursed and fumed under his breath and led the way to an inner courtyard where stood four immense black boxes painted with death-heads, splintered bones, fountains of blood and cabalistic symbols all of a sinister appearance.

“Those swine in Appsala take our water-of-power and give nothing in return. Oh yes, they let us use their engines, but after running for a few months the cursed things stop and will not go again, then we must bring them back to the city to exchange for a new one, and pay again and again.”