'Or gold,' Sayyed Abdul Aziz joked.
'Or gold. In that case the cannonballs veer only slightly, but over the great distances they are cast, it becomes significant. And so one can never say exactly what the balls will hit.'
'This must ever be true,' Nadir said.
Khalid waved his stump, oblivious for the moment of how it looked. 'We can reduce the effect quite a great deal. See how the wooden balls fly if they are cast with a spin to them.'
Bahram and Paxtakor threw the balsam balls with a final pull of the fingertips to impart a spin to them. Though some of these balls curved in flight, they went farther and faster than the palmed balls had. Bahram hit an archery target with five throws in a row, which pleased him greatly.
'The spin stabilizes their flight through the wind,' Khalid explained. 'They are still pushed by the wind, of course. That cannot be avoided. But they no longer dart unexpectedly when they are caught on the face by a wind. It is the same effect you get by fletching arrows to spin.'
'So you propose to fletch cannonballs?' the Khan inquired with a guffaw.
'Not exactly, your Highness, but yes, in effect. To try to get the same
kind of spin. We have tried two different methods to achieve this. One is to cut grooves into the balls. But this means the balls fly much less far. Another is to cut the grooves into the inside of the gun barrel, making a long spiral down the barrel, only a turn or a bit less down the whole barrel's length. This makes the balls leave the gun with a spin.'
Khalid had his men drag out a smaller cannon. A ball was fired from it, and the ball tracked down by the helpers standing by, then marked with a red flag. It was farther away than the bigger gun's ball, though not by much.
' It is not distance so much as accuracy that would be improved,' Khalid explained. 'The balls would always fly straight. We are working up tables that would enable one to choose the gunpowder by type and weight, and weigh the balls, and thus, with the same cannons, of course, always send the balls precisely where one wanted to.'
'Interesting,' Nadir said.
Sayyed Abdul Aziz Khan called Nadir to his side. 'We're going back to the palace,' said, and led his retinue to the horses.
'But not that interesting,' Nadir said to Khalid. 'Try again.'
Better Gifts for the Khan
'I suppose 1 should make the Khan a new suit of damasked armour,' Khalid said afterwards. 'Something pretty.'
lwang grinned. 'Do you know how to do it?'
'Of course. It's watered steel. Not very mysterious. The crucible charge is an iron sponge called a wootz, forged into an iron plate together with wood, which yields its ash into the mix, and some water too. Some crucibles are placed in the furnace, and when they are melted their contents are poured into molten cast iron, at a temperature below that of complete fusion of the two elements. The resulting steel is then etched with a mineral sulphate of one kind or another. You get different patterns and colours depending on which sulphate you use, and what kind of wootz, and what kind of temperatures. This blade here,' he rose and took down a thick curved dagger with an ivory handle, and a blade
covered with a dense pattern of crosshatchings in white and dark grey, 'is a good example of the etching called "Mohammed's Ladder". Persian work, reputed to be from the forge of the alchemist Jundi‑Shapur. They say there is alchemy in it.' He paused, shrugged.
'And you think the Khan . . .'
'If we systematically played with the composition of the wootz, the structure of the cakes, the temperatures, the etching liquid, then we would certainly find some new patterns. 1 like some of the swirls I've got with very woody steel.'
The silence stretched out. Khalid was unhappy, that was clear.
Bahram said, 'You could treat it as a series of tests.'
'As always,' Khalid said, irritated. 'But in this case you can only do things in ignorance of their causes. There are too many materials, too many substances and actions, all mixed together. I suppose it is all happening at a level too small to see. The breaks you see after the casting look like crystalline structures when they are broken. It's interesting, what happens, but there's no way to tell why, or predict it ahead of time. This is the thing about a useful demonstration, you see. It tells you something distinct. It answers a question.'
' We can try to ask questions that steelwork can answer,' Bahram suggested.
Khalid nodded, still dissatisfied. But he glanced at Iwang to see what he thought of this.
lwang thought it was a good idea in theory, but in practice he too had a hard time coming up with questions to ask about the process. They knew how hot to make the furnace, what ores and wood and water to introduce, how long to mix it, how hard it would turn out. All questions on the matter of practice were long since answered, ever since damasking had been done in Damascus. More basic questions of cause, which yet could be answered, were hard to formulate. Bahram himself tried mightily, without a single idea coming to him. And good ideas were his strength, or so they always told him.
While Khalid worked on this problem, lwang was getting terrifically absorbed in his mathematical labours, to the exclusion even of his glassblowing and silversmithing, which he left mostly to his new apprentices, huge gaunt Tibetan youths who had appeared without
explanation some time before. He pored over his Hindu books and old Tibetan scrolls, marking up his chalk slates and then adding to the notes he saved on paper: inked diagrams, patterns of Hindu numerals, Chinese or Tibetan or Sanskrit symbols or letters; a private alphabet for a private language, or so Bahram thought. A rather useless enterprise, disturbing to contemplate, as the paper sheets seemed to radiate a palpable power, magical or perhaps just mad. All those foreign ideas, arranged in hexagonal patterns of number and ideogram; to Bahram the shop in the bazaar began to seem the dim cave of a magus, fingering the hems of reality ...
Iwang himself brushed all these cobwebs aside. Out in the sun of Khalid's compound he sat down with Khalid, and Zahhar and Tazi from Sher Dor, and with Bahram shading them and looking over their shoulders, he outlined a mathematics of motion, what he called the speed‑of‑the‑speed.
'Everything is moving,' he said. 'That is karma. The Earth revolves around the Sun, the Sun travels through the stars, the stars too travel. But for the sake of study here, for demonstrations, we postulate a realm of non‑movement. Perhaps some such motionless void contains the universe, but it doesn't matter; for our purposes these are purely mathematical dimensions, which can be marked by vertical and horizontal, thusly, or by length, breadth and height, if you want the three dimensions of the world. But start with two dimensions, for simplicity's sake. And moving objects, say a cannonball, can be measured against these two dimensions. How high or low, how left or right. Placed as if on a map. Then again, the horizontal dimension can mark time passed, and the vertical, movement in a single direction. That will make for curved lines, representing the passage of objects through the air. Then, lines drawn tangent to the curve indicate the speed of the speed. So you measure what you can, mark those measurements, and it's like passing through rooms of a house. Each room has a different volume, like flasks, depending on how wide and how tall. That is to say, how far, in how much time. Quantities of movement, do you see? A bushel of movement, a dram.'
'Cannonball flights could be described precisely,' Khalid said.
'Yes. More easily than most things, because a cannonball pursues a single line. A curved line, but not something like an eagle's flight, say,
or a person in his daily rounds. The mathematics for that would be . . .' Iwang became lost, jerked, came back to them. 'What was I saying?'
'Cannonballs.'
'Ah. Very possible to measure them, yes.'
'Meaning if you knew the speed of departure from the gun, and the angle of the gun . . .'
'You could say pretty closely where it was going to land, yes.'
'We should tell Nadir about this privately.'
Khalid worked up a set of tables for calcu
lating cannon fire, with artful drawings of the curves describing the flight of shot, and a little Tibetan book filled with lwang's careful numerics. These items were placed in an ornate carved ironwood box, encrusted with silver, turquoise and lapis, and brought to the Khanaka in Bokhara, along with a gorgeous damasked breastplate for the Khan. The steel rectangle at the centre of this breastplate was a dramatic swirl of white and grey steel, with iron flecks very lightly etched by a treatment of sulphuric acids and other caustics. The pattern was called by Khalid the Zeravshan Eddies, and indeed the swirl resembled a standing eddy in the river, spinning off the foundation of the Dagbit Bridge whenever the water was high. It was one of the handsomest pieces of metalwork Bahram had ever seen, and it seemed to him that it, and the decorated box filled with lwang's mathematics, made for a very impressive set of gifts for Sayyed Abdul Aziz.
He and Khalid dressed in their best finery for their audience, and lwang joined them in the dark red robes and conical winged hat of a Tibetan monk, indeed a lama of the highest distinction. So the presenters were as impressive as their presents, Bahram thought; although once in the Registan, under the vast arch of the goldcovered Tilla Karia Madressa, he felt less imposing. And once in the company of the court he felt slightly plain, even shabby, as if they were children pretending to be courtiers, or, simply, bumpkins.
The Khan, however, was delighted by the breastplate, and praised Khalid's art highly, even putting the piece on over his finery and leaving it there. The box he also admired, while handing the papers inside to Nadir.
After a few moments more they were dismissed, and Nadir guided them to the Tilla Karia garden. The diagrams were very interesting, he
said as he looked them over; he wanted to inquire more closely into them; meanwhile, the Khan had been informed by his armourers that cutting a spiral into the insides of their cannon barrels had caused one to explode on firing, the rest to lose range. So Nadir wanted Khalid to visit the armourers and speak to them about it.
Khalid nodded easily, though Bahram could see the thought in his eyes; once again he would be taken away from what he wanted to be doing. Nadir did not see this, though he watched Khalid's face closely. In fact, he went on cheerfully to say how much the Khan appreciated Khalid's great wisdom and craft, and how much all the people of the Khanate and in Dar al‑Islam generally would owe to Khalid if, as seemed likely, his efforts helped them to stave off any further encroachments of the Chinese, reputed to be on the march in the west borders of their empire. Khalid nodded politely, and the men were dismissed.
Walking back along the river road, Khalid was irritated. 'This trip accomplished nothing.'
'We don't know yet,' lwang said, and Bahram nodded.
'We do. The Khan is a . He sighed. 'And Nadir clearly thinks of us as his servants.'
'We are all servants of the Khan,' lwang reminded him.
That silenced him.
As they came back towards Samarqand, they passed by the ruins of old Afrasiab. 'If only we had the Sogdian kings again,' Bahram said.
Khalid shook his head. 'Those are not the ruins of the Sogdian kings, but of Markanda, which stood here before Afrasiab. Alexander the Great called it the most beautiful city he ever conquered.'
'And look at it now,' Bahram said. 'Dusty old foundations, broken walls . . .'
lwang said, 'Samarqand too will come to this.'
'So it doesn't matter if we are at Nadir's beck and call?' Khalid snapped.
'Well, it too will pass,' lwang said.
jewels in the Sky
Nadir asked for more and more of Khalid's time, and Khalid grew very restive. One time he went to Devanbegi with a proposal to build a complete system of drains underneath both Bokhara and Samarqand, to move the water of the scores of stagnant pools that dotted both cities, especially Bokhara. This would keep the water from becoming foul, and decrease the number of mosquitos and the incidence of disease, including the plague, which the Hindu caravans reported to be devastating parts of Sind. Khalid suggested sequestering all travellers outside the city whenever they heard such news, and causing delays in caravans that came from affected areas, to be sure of cleanliness. A purification delay, analogous to the spiritual purifications of Ramadan.
But Nadir ignored all these ideas. An underground system of pipes, though common in Persia from before the invasions of the Mongols, was too expensive now to contemplate. Khalid was being asked for military aid, not physic. Nadir did not believe he knew anything about physic.
So Khalid returned to his compound and put the whole place to work on the Khan's artillery, making every aspect of the cannons a matter for demonstrations, but without trying to learn anything of primary causes, as he called them, except occasionally in motion. He worked on metal strength with Iwang, and made use of lwang's mathematics to do cannonflight studies, and tried a number of methods to cause the cannonballs to spiral reliably in flight.
All this was done with reluctance and ill‑humour; and only in the afternoon, after a nap and a meal of yoghurt, or late in the evening, after smoking from one of his narghiles, did he recover his equanimity, and pursue his studies with soap bubbles and prisms, air pumps and mercury scales. 'If you can measure the weight of air you should be able to measure heat, up to temperatures far beyond what we can distinguish with our blisters and ouches.'
Nadir sent his men by on a monthly basis to receive the latest news of Khalid's studies, and from time to time dropped by himself
unannounced, throwing the compound into a flurry, like an anthill hit by water. Khalid was polite at all times, but complained to Bahram bitterly about the monthly request for news, particularly since they had very little. 'I thought 1 escaped the moon curse when Fedwa went through menopause,' he groused.
Ironically, these unwelcome visits were also losing him allies in the madressas, as he was thought to be favoured by the treasurer, and he could not risk telling them the real situation. So there were cold looks, and slights in the bazaar and the mosque; also, many examples of grasping obsequiousness. It made him irritable, indeed sometimes he rose to a veritable fury of irritability. 'A little power and you see how awful people are.'
To keep him from plunging back into black melancholy, Bahram scoured the caravanserai for things that might please him, visiting the Hindus and the Armenians in particular, also the Chinese, and coming back with books, compasses, clocks, and a curious nested astrolabe, which purported to show that the six planets occupied orbits that filled polygons that were progressively simpler by one side, so that Mercury circled inside a decagon, Venus a nonagon just large enough to hold the decagon, Earth an octagon outside the nonagon, and so on up to Saturn, circling in a big square. This object astonished Khalid, and caused nightlong discussions with lwang and Zahhar about the disposition of the planets around the sun.
This new interest in astronomy quickly superseded all others in Khalid, and grew to a passion after lwang brought by a curious device he had made in his shop, a long silver tube, hollow except for glass lenses placed in both ends. Looking through the tube, things appeared closer than they really were, with their detail more fine.
'How can that work?' Khalid demanded when he looked through it. The look of surprise on his face was that of the puppets in the bazaar, pure and hilarious. It made Bahram happy to see it.
'Like the prism?' lwang suggested uncertainly.
Khalid shook his head. 'Not that you can see things as bigger, or closer, but that you can see so much more detail! How can that be?'
'The detail must always be there in the light,' lwang said, 1 and the eye only powerful enough to discern part of it. I admit 1 am surprised, but consider, most people's eyes weaken as they age, especially for things
close by. 1 know mine have. 1 made my first set of lenses to use as spectacles, you know, one for each eye, in a frame. But while 1 was assembling one 1 looked through the two lenses lined up together.' He grinned, miming the action. 'I was really very anxious to confirm that you two saw the same
things I saw, to tell the truth. 1 couldn't quite believe my own eyes.'
Khalid was looking through the thing again.
So now they looked at things. Distant ridges, birds in flight, approaching caravans. Nadir was shown the glass, and its military uses were immediately obvious to him. He took one they had made for him, encrusted with garnets, to the Khan, and word came back that the Khan was pleased. That did not ease the presence of the Khanate in Khalid's compound, of course; on the contrary, Nadir mentioned casually that they were looking forward to the next remarkable development out of Khalid's shop, as the Chinese were said to be in a turmoil. Who knew where that kind of thing might end?
'It will never end,' Khalid said bitterly when Nadir had gone. 'It's like a noose that tightens with our every move.'
'Feed him your discoveries in little pieces,' Iwang suggested. 'It will seem as if there are more of them.'
Khalid followed this advice, which gave him a little more time, and they worked on all manner of things that it seemed would help the Khan's troops in battle. Khalid indulged his interest in primary causes mostly at night, when they trained the new spyglass on the stars, and later that month on the moon, which proved to be a very rocky, mountainous, desolate world, ringed by innumerable craters, as if fired upon by the cannon of some super‑emperor. Then on one memorable night they looked through the spyglass at Jupiter, and Khalid said, 'By God it's a world too, clearly. Banded by latitude ‑ and look, those three stars near it, they're brighter than stars. Could they be moons of Jupiter's?'
The Years of Rice and Salt Page 30