Land of the Burning Sands (13 page)

“Because anyone knows that some very strong materials like stone can tolerate hardly any kind of crack at all before they break under tension, which is why you can build with wrought iron under tension but you always put stone under compression, yes? So we really need to think of resistance to crack propagation as a property related not to strength exactly, but to the forcefulness of the blow it takes to fracture a piece of the material, do you see? What I think—” tapping the row of equations once more, she seemed suddenly to wonder whether Gereint was following this, and stopped, looking at him with doubt.

Gereint said, “I haven’t worked extensively with bridges or walls, but I’d think that what you need most is proper definitions of qualities like ‘strength’ and ‘forcefulness’ and ‘toughness’ and ‘brittleness’ and ‘flexibility.’ And ‘stretchability,’ once you start thinking about metals, because once you start thinking about crack propagation through metal, it’s probably ‘stretchability’ that allows for greater resistance to fracture, don’t you think?”

Tehre gazed at Gereint as though actually seeing him for the first time. Her eyes, an unusual bronzy green, were large and striking in her delicate face.

Then she flipped open a large book on the nearest table, paged through it rapidly until she reached blank paper, and picked up a quill. “The length of a ‘safe’ crack in a structure must depend on the ratio of its ‘brittleness’ to the amount of tensile force applied to the material,” she said, writing quickly. “No! Not the amount of tensile force
applied
, but the amount actually
absorbed
by the material. And so the critical length of a crack would actually be inversely proportional to the ‘stretchability’ of the material.” She paused and blinked down at the book. “That seems counterintuitive. But isn’t that right?”

Gereint said, “It follows, but it means you need a term for ‘toughness’ as well as one for ‘stretchability.’ One is more like resistance to fracture as a result of a blow, isn’t it, and the other is more like resilience under tension. Or is that right?”

“I can see you two will do well,” said Fareine. “But, Tehre, don’t forget, you still need to eat one of these nice sandwiches.”

“What?” Tehre turned to the old woman and stared at her for a moment before actually focusing on her. Then she laughed.

Gereint was surprised at that laugh. It was a nice laugh, filled with affection and genuine amusement—at herself, at her own intensity and distractibility. It occurred to him that Tehre might well borrow a word like “distractibility” to mean “ability to slip under friction” or something of the sort, and he smiled.

“We’ll go out to the garden, I suppose,” Tehre suggested. “Fareine, is everything”—she waved her hands vaguely, still holding the quill—“in order?”

“Your guest is properly settled,” Fareine assured her mistress. “Thank you, honored sir; if you could take these plates, I’ll go fetch jugs of wine and water, shall I?” She handed over the sandwiches and cakes and bustled out again.

Gereint raised his eyebrows at Lady Tehre, meaning
Which way?

“Through here,” the lady said, swinging back a small door. She immediately went on, walking backward through the doorway into brilliant sunlight and catching herself with the automatic skill of long practice when she tripped over the step. “You’re a maker, did Fareine say? Or an engineer?”

“A maker, primarily. But I was wondering the same about you, since you seemed to be thinking about building large structures…”

“Neither the one nor the other,” the woman said, a little bitterly. She looked around, seemed to spot a nearby shaded bench as though it was the first time she’d ever seen it, and sat down. Gereint followed, offering her the plate of sandwiches again, since she seemed to have forgotten about it.

“Or maybe both,” added Tehre, taking a sandwich and gazing thoughtfully down at it. She was still thinking about Gereint’s question, evidently. He hadn’t meant it to be so complicated. But the woman said absently, “A maker and a builder and an engineer and a philosopher…” She looked suddenly up at Gereint. “I’m trying to understand how things work. But some important concepts are”—she made a frustrated gesture with the sandwich—“missing. I’m sure if I just define my terms properly… You’re quite right, by the way, that’s the first thing that has to be done, but you have to work with the concepts before you see what you need names for…”

“I have business of my own in the city, so your father was kind enough to suggest you might wish to offer me a guest room while I’m here,” Gereint said after a moment, as the lady did not seem inclined to go on with her thought.

“Yes, of course, if you like,” Tehre said, but Gereint had the impression she hadn’t really heard him.

“Are you going to eat that, or just wave it around? Meat is expensive since the refugees from Melentser started arriving, you know,” Fareine added, returning with the promised jugs and a pair of goblets.

“Oh,” said Tehre, and took a bite. But her attention remained on Gereint. No wonder she was so small, if she never ate anything without being prompted.

“Wine, honored sir?” Fareine poured for her lady and Gereint and for herself, a little wine and a good deal of water, and then settled on the end of Tehre’s bench.

“What do you make?” Tehre asked Gereint abruptly.

“Small things, mostly. But all kinds of things. Knives and lanterns, belts and boots, pots and plates…”

The woman laughed, unexpectedly. It was the same laugh as before, quick and genuinely amused. “Not a specialist! All right. I’m mostly working philosophically right now—with the philosophy of stone and iron and wood, with the building materials of the world.” She sighed. “It’s hard to actually
practice
building large structures just to see how they’ll break if you apply different kinds of stresses. Have you read Wareierchen?”

“Yes,” Gereint said promptly. “And Dachsechreier’s
Making with Wood
, and Garaneirdich’s
The Properties of Materials
. What do you think of Terichsekiun?”

Tehre’s small face lit up, giving her, at last, the misleading appearance of uncomplicated prettiness. “Oh, his
Strength of Materials
is so fascinating! It’s so interesting that cast iron acts so much like stone, isn’t it, and so different from wrought iron?” She took another bite of her sandwich and chewed absently, lost in thought.

“You seem to have been thinking about bridges,” Gereint commented, and was entertained to see how Lady Tehre was instantly distracted. She jumped to her feet, set her sandwich aside half finished, said, “I’ll show you; come look!” and started back toward the workroom.

Fareine, looking resigned, gathered the half-sandwich up in a cloth and followed her mistress. Gereint picked up the platter, since it didn’t seem proper to simply leave it sitting on the bench, and followed them both.

The diagrams were very interesting. There were large, detailed drawings of bridge after bridge—short, flat, beam-supported bridges across narrow gullies; high-rising arches across streams; rope-supported plank bridges that looked extremely precarious. Some of the bridges were made of many small arches, some supported merely at either end.

“Are these all after real bridges?” Gereint asked, leaning over a particularly unusual bridge made of open latticework in a single extremely long, flat arch. “This can’t really be to scale?”

“Oh, it is, though! That one’s from Linularinum—it crosses that river at Teramondian, you know, the Meralle? Terichsekiun referred to it and had a small drawing, but this one is more accurate and much more detailed. It cost a fortune, sending a man all the way to Linularinum to draw it for me, but it was worth it. See, this bridge has a span of a hundred fifty-nine feet, but a rise of only twenty-six feet. It’s made of cast iron, so it’s lighter than masonry would be, do you see? And that means it pushes sideways against its foundations much less than masonry would, which is why Terichsekiun says it works, but I’m not sure that’s the whole answer.” She bent intently over the diagram.

Gereint watched Tehre Amnachudran study one part of the diagram and then another and then absently pick up a quill and begin working out equations in the blank space along the edge of the paper, and wondered why she’d had such trouble finding other makers to work with her. She was obsessive, yes. But what she was trying to work out was very interesting. Surely any real maker would think so?

And, also… he clearly did not need to worry that this woman would prove very interested in who
he
was or where
he’d
come from. It hadn’t even occurred to her to wonder. Ah. That might explain a great deal, after all. That lack of interest might well offend any man who believed all women ought to find him naturally fascinating.

Gereint merely found the lack of curiosity reassuring. Restful. He glanced at Fareine, who gave him a friendly smile and stayed in the background, possibly to run any errands her mistress thought of, but more likely as a guarantor of respectability.

Tehre brought out a new diagram and pinned it open across the others. This one also showed a bridge, but not like the others. This one had chains suspended from two high, parallel semi-circular arches and a roadway of beams suspended from the chains.

“That’s unusual,” Gereint observed, examining the diagram. “Where’s this one from?”

Tehre gave him a glance that had gone suddenly shy. “Oh, well… I made this one up. When I was thinking about the differences between cast iron and wrought iron and steel, and about the bridges they’ll need to build when they run that road through the mountains. It’s supposed to be a real road, you know, the kind that will gladden the Arobern’s ambitious heart—four wagons abreast and all the fretwork to match.” Despite her acerbic tone, she sounded like she would enjoy a chance to test out some new ideas in the building of a really fine road.

“Steel wire is what I’d like to use for this,” Tehre added. “Only that would be much too expensive, of course. So I worked it out for wrought-iron chains. Only you’d have to have
very
good makers to make those chains and bolt them to the decking of the road—I designed that like the deck of a ship, in a way. I’d like to show you the kind of bolts I have in mind and see what you think—have you worked with wrought iron?”

“I’ve worked with everything,” Gereint assured the woman.

“Have you? That’s good,” Tehre said absently. She looked around vaguely. Fareine came forward and put her half-full mug of watered wine in her hand. Tehre gazed at the older woman for a moment; then down at the mug she held with much the same air of vague surprise and sipped.

“You should eat the rest of your sandwich, too,” Fareine said, offering it.

“I suppose.” Tehre allowed the woman to press it on her.

“Cakes, honored sir?” Fareine offered him the other platter.

“Don’t get honey on the diagrams!” Tehre exclaimed, and then, with sudden pleasure, “Oh, are there cakes? Thank you, Fareine, but mind the honey.”

The older woman smiled patiently and passed around damp cloths to take care of the honey.

“So,” Tehre said to Gereint, and then paused as though unsure how to proceed. Then she asked cautiously, as though it was a potentially dangerous question, “So have you worked on bridges before? Or the ways structures fail?”

“Not specifically,” Gereint admitted. “It sounds interesting, though.”

“Everything’s interesting,” Tehre responded. She didn’t say it as though she was making a joke; there was nothing arch or sidelong or humorous in her tone. She just said it.
Everything’s interesting
, exactly as though she meant precisely that. Then she added, more wistfully, “But I do think I’m missing something: some fundamental concept that would let me see more clearly how bridges and walls and ships and little mechanisms like bows and clocks and dumbwaiters all work. I think I’m missing something that would help explain bridges and crack propagation and, and, I don’t know. Why ropes break and stone shatters and metals bend.” She ate a cake in two impatient bites, gazing moodily down at the diagram on the table.

“I’ve been mostly in the practical end of making,” Gereint told her. “But I think you’re asking good questions. You can tell me what you think about strength and cracks and resilience, and maybe I can help you come up with proper definitions of the qualities of materials. Why should Garaneirdich and Wareierchen and Terichsekiun have all the fun? Though maybe the first task is to clarify what all those great philosophers said and see how their terms match up to each other and the qualities you want to define.”

Tehre gazed at Gereint with, possibly, the first real attention she’d paid him. “You’ve read all the philosophers? Yes, you have, haven’t you? You’d understand what you read and summarize properly?”

She sounded doubtful on this last, as though, if put to the test, he’d possibly prove to be functionally illiterate. Gereint tried not to smile. He said gravely, “I think so, yes.”

“Well, then. Well, then, if you could do that for me—exactly what you said—I have these equations I’m trying to work out—it would save me a great deal of time and then, you’re right, maybe it would be easier to see what qualities are already defined and what Wareierchen and Terichsekiun might have missed—does that sound too arrogant?” she added, once again doubtful.

Gereint tried, again, not to smile. It was getting harder. “Not to me.”

“All right. Good. Good! I’ll show you my library, then. Or Fareine—Fareine! Would you show, ah…”