Having decided to hold off on the residential buildings until he could bring his capacity up to scratch, Alexander issued the task he came here for.
"Diaogosis, let's get to the real reason I called you," Alexander said, drawing a surprised look from the stonemason, who thought about a few alternative situations about why Alexander would make such a statement.
But he did not get too far into his thoughts as Alexander handed him a piece of paper with some drawings.
"Here, read this. And see if you can understand them," He instructed.
"Oh! Is this the famed 'paper' that the lord has invented?" Diaogosis quickly accepted the white sheet, rubbing it between his fingers and exclaiming, "So soft! And so sturdy! Nothing like the papyrus."
He seemed more interested in the novelty of the paper than what was actually written on it.
"....," Alexander simply waited and gave the man a bit of time to check out the new invention.
Diaogosis savored the smooth texture and gazed at the pristine white sheet, and even sniffed the new paper smell for a while, after finally which the feeling of novelty ran out and he decided to focus his attention on what was written on the paper itself.
He knew wherever his lord would hand over things like this, it almost always be about new inventions and gadgets, and he felt giddy thinking about what new contraption and contrivance the pasha had cooked up this time.
And as he eagerly turned his eyes to the paper, he found it was just as he had predicted- it was a new invention.
More specifically it was the blueprints of what seemed to be a huge wheel over which water seemed to be flowing causing this huge spooked circle to spin.
And below it was the label- Waterwheel.
"The flowing water will cause the wheel called the millwheel to spin." Alexander began his explanation, "Which can be attached to something like a wheat milling wheel so it will spin with it, and thus milling the wheat automatically."
Alexander's short description was enough to make the artisan understand the invention's significance and he exclaimed, "Oh my lord, this is fantastic! With this installed near rivers and springs, we will be able to mill wheat like we were breathing."
Diaogosis was able to instantly grasp where the waterwheel was supposed to be placed showing the man's skill and expertise.
And then laughed out, "Haha, using this we can half the price of wheat. The people are certain to rejoice,"
He was happy that he had found the excuse by which the people will forget Alexander's little delay with the houses.
And while he certainly exaggerated about the price fall, the waterwheel would certainly be used like that.
But Alexander's intention to use the thing was far more industrial.
"Mnnn, the waterwheel can certainly be used and will be used to grind wheat...later" Alexander said the last word with a bit of a pause, adding with this his characteristic 'but'. "But for now, these ones will be used to crush the clinkers."
"Crush cement?" Being the largest consumer of cement he certainly knew the products from the kiln needed to be crushed.
That was not what surprised him, but this, "My lord, I don't think simply substituting the stone clinkers for wheat grains in the mill will work."
And then he reasoned, "Those tiny stones are much harder than the grain and will either not break, get stuck between the wheels, or the powder will not be fine enough."
There was certainly logic behind Diaogosis's skepticism.
And to understand that one needed to understand how a millstone worked.
The way this simple but vital machine worked was that there was a stationary stone wheel called the static bedstone sitting at the base, with a moving stone wheel called the runnerstone was placed on top of it.
And almost counter-intuitively, these two millstones did not touch when in operation, and a small gap was kept in between them that was adjustable and was determined on a day to day to basis depending on the size of the grain.
The runnerstone had a small hole in the center of it called the eyes through which grains could be inserted, and as the stone was spun, an intricate system of groves known as furrows distributed the grain across the millstone's bottom surface, and also served to ventilate and cool the millstones.
These grains would then be crushed using an intricate pattern on the millstone's surface that was between the furrows and once ground the flour passed along narrow groves called cracking, and was expelled from the edge of the millstones.
Hence, Diaogosis rightly feared that, though the weight of the moving stone and the friction between the two surfaces was enough to crush the relatively soft grains, the solid, stone-like clinkers would get stuck between these narrow channels or even outright ruin the thin grooves due to the clinkers inherent hardness, thus posing themselves as too hard to milled by traditional means.
"Mnnn, you are right," Alexander too agreed with these fears.
But then added, "That's why we will not do it like that."
The confident tone in Alexander's voice gave the clue that he already had the idea about how to overcome this challenge and so Diaogosis kind of jumped the gun and eagerly asked with anticipation, "Oh, then how will the clinkers be crushed?"
His eyes seemed to be sparkling as he asked this.
"Hahaha, first let me tell you how to build the waterwheel," Alexander decided to finish the waterwheel topic first before moving on to the new topic, thus keeping the shroud of secrecy around the new crushing technique around for a little longer.
"Ah! Yes, yes, my lord," Diaogosis quickly replied, letting out an embarrassed chuckle, "Haha, I seemed to have gotten too ahead of myself."
"Mmm, then regarding building the waterwheel," Alexander thus began, "This type of waterwheel, where the water flows from the top is called the overshot waterwheel. And if the water flows horizontally like from a river, it is called an undershot waterwheel."
"We will build both. But first, let's look at how to build the overshot waterwheel." Alexander pointed at the paper.
"To build this type of waterwheel, first you will need to build these things," Diaogosis saw Alexander's fingers direct his eyes to small lines that he presumed to be flat wooden planks between the rims.
"These might look like wooden paddles, but really they are buckets," Alexander clarified, explaining, "The water will flow from the spring or dam, fill up the empty buckets which will cause them to become heavier and fall down, pushing the empty, lighter buckets at the opposite of side up top"
"Once the filled buckets reach the bottom, the inertia of the wheel and the force of the water will tip the buckets over, causing them to deposit their water out and make the buckets lighter, which can be again pushed up by the succeeding heavier buckets, thus repeating the cycle." Alexander gave a simple, generalized overview of how a waterwheel worked.
"To think Your Grace would have thought so deeply. I at best could have made the buckets like solid panels, similar to oars in a boat," Diaogosis let out a genuine exclamation of praise, wholeheartedly conceding that Alexander was a superior artisan to him.
He had observed even before that Alexander could not only think of new inventions but also make small adjustments within those inventions that might seem insignificant additions to a layman's eyes but improved the performance of the contraption by significant margins.
But it would be too wrong for Diaogosis to disparage himself too much as he was no slouch either, for few possessed the ability to tell at a glance or just from hearing the description, why using buckets instead of straight blades or paddles were better.
Diaogosis, though did not fully comprehend the existence of gravity, could intuitively understand this type of structure will not only use the speed of the water striking the wheel to spin but also use the additional weight of water going down, making the wheel spin faster.
Alexander had learned the details about the waterwheel, both the overshot and undershot from a science project in his high school, a topic got handed to him by a class lottery, one which asked him to explore some real-life examples of the usage of gravitational potential energy.
And the project had been quite extensive, making him learn much about watermills, how they worked, what kind of equations were used to calculate their output, their factors of efficiency, and hundreds of other peripherally.
"So where does my lord what to build this? And how big? Diaogosis was very enthusiastic about the whole thing, understanding this was Alexander's way of giving him an alternative path to making contributions.
"I have not finished," Alexander gently chided, feeling a bit peeved at being interrupted.
"..." Diaogosis only produced a little flush and quickly stooped down his head to hide this as he deeply concentrate on the paper he was holding.
" Now, these buckets" Alexander once again started, "They will be stuck to each other at a 45-degree angle," Alexander showed this by tilting his palms, forming his fingers that resembled a military salute.
The concept of angles was something these people understood very well, and so Diaogosis nodded understandingly, though this time did not open his mouth for fear of going off-topic, only looking down at the diagram to confirm what Alexander was saying matched the instructions that were already written on the paper.