At Lucius Caesar's words, the blacksmiths simply scoffed.
"Wait, so the boy is going to teach us how to work a forge?"
"I've heard tales of the young Caesar inventing all sorts of things, but come on, what could he possibly know about smithing?"
"Our travel and lodging have already been paid for, so hearing him out costs us nothing."
These were some of the finest master smiths in Italy, men who had worked at the anvil since childhood.
Most were freeborn, while several were freedmen who had earned their freedom through sheer skill.
"It couldn't hurt to hear him out, at least."
"True enough. I heard Lucius runs some kind of technical school where he trains craftsmen and engineers."
"You can't just teach smithing in a classroom."
"Agreed. I've heard the rumors about his waterwheels plenty of times, but aren't we already using those?"
The next morning, the men gathered at a site upstream on the Tiber.
Four massive waterwheels greeted them, churning steadily in time with the river's current.
"So these are the famous Caesar waterwheels."
"Look at what it's connected to."
One of the blacksmiths pointed toward the rear of the workshop.
Beside it stood a large smelting furnace.
Built from clay and stone, the structure stood as tall as two men, with large leather bellows attached to its side.
But no one was pumping those bellows.
With every turn of the waterwheel's axle, a wooden lever compressed the bellows, making them exhale like a living beast.
"You can drive bellows with a waterwheel?"
The blacksmiths observed the mechanism with genuine intrigue.
A waterwheel itself wasn't a strange sight.
But using its continuous power to drive bellows and feed air into a furnace without anyone pumping them by hand? That was entirely unheard of for the blacksmiths of Rome.
Just then, Lucius Caesar appeared before them.
"This is an experimental forge, built specifically to demonstrate something to all of you."
He added,
"I do not presume to forge better steel than any of you. But what if I told you that I had found a way to produce larger quantities of iron with more consistent quality than ever before?"
"And you're saying you'll teach us how?"
"Yes. But the method still has plenty of room for improvement, which is why I need your help."
Lucius nodded.
"You are the only ones qualified to judge whether my method is right or wrong."
As the craftsmen exchanged wary glances, Lucius ushered them into the workshop.
"Shall we begin?"
＊＊＊
The iron and steel produced in Roman times were very different from the steel that came out of twenty-first-century mills.
Roman bloomeries did not normally produce fully liquid iron. Instead, they yielded a spongy mass of iron mixed with slag and other impurities—a bloom.
Smiths would then reheat and hammer the bloom repeatedly to drive out the slag. To harden selected pieces, they could heat the iron for a long time in a charcoal-rich fire, allowing it to absorb carbon.
Only then could the smith produce material ranging from wrought iron to steel.
Naturally, the carbon content and overall quality varied wildly during the smelting process, meaning the final product's quality depended entirely on the individual smith's skill.
"Why don't you try smelting iron from the ore yourselves, right here?"
At my suggestion, the blacksmiths all exchanged awkward looks.
"Right here?"
"Yes. I will provide all the materials you need, and I will pay you separately for your work."
"Well, that sounds great for us, but..."
The blacksmiths warily eyed one another.
Ah, I hadn't thought about that part.
Master craftsmen were dead serious about protecting their secrets. They wouldn't want to expose their personal techniques in front of their direct competitors.
"Then how about we set up a schedule so each of you can use the facility in private? Of course, if you don't wish to participate, you are free to return home right now."
Interestingly enough, not a single one of them declined the offer.
As the blacksmiths scattered to inspect the experimental forge I had built, Vitruvius and I watched them closely.
"This is quite fascinating."
Vitruvius murmured.
"I had no idea the methods varied this much from smith to smith."
I nodded instead of answering. The craftsmen inspected the piles of ore before even looking at the furnace.
Some weighed the chunks of iron ore in their hands, while others struck pieces together to listen to the sound.
One even cracked a piece open with a hammer.
"This one has too much dirt in it."
"This charcoal would be better ground into a fine powder."
I trailed after them, tossing out questions here and there.
No matter how much knowledge I carried from the future, I still had many blind spots when it came to how craftsmen of this era actually worked.
"Do you sort the charcoal by type before using it?"
"Large chunks are good for the furnace. But if the charcoal is too small, it chokes the airflow and turns to ash too quickly."
A blacksmith nodded as he replied.
"Fine charcoal dust is useful for brick or lime kilns. But you should never dump it into a smelting furnace."
Vitruvius stood by my side, meticulously recording every answer the smiths gave.
Anyone watching would have thought we were conducting an examination.
"Using the waterwheel to drive an ore stamp is a clever idea, but the crushing bed will not last long like this. Reinforce its base with a heavy iron plate. Better yet, fit it with a replaceable plate so it can be changed once it wears through."
"That's a brilliant idea. I'll definitely look into it."
Though awkward at first, the blacksmiths began to voice their opinions more freely as time went on.
"The most crucial moment is when you pull the iron from the fire. Quench it too quickly, and it may become brittle. Cool it too slowly, and it will remain too soft. Keep a vat beside the forge so you can quench the metal in water or oil at the right moment."
From Etruria to Campania, from Cisalpine Gaul all the way to Sicily.
Blacksmiths from different regions prioritized completely different techniques.
"There is far more here that needs improving than I expected. If anything, we are the ones learning the most."
"True, but now they know it's possible to forge iron in a completely new way,"
I replied.
Using a waterwheel made working with iron much easier.
Striking metal by hand with a hammer was completely different from harnessing the raw power of moving water.
The craftsmen realized the potential of water power, and I learned a slew of practical improvements. It was a win-win situation.
"It is a shame they are not a little friendlier with one another, though."
I said.
Well, I suppose hoping for direct competitors to play nice was a bit of a stretch.
＊＊＊
Ironically, the news that Lucius Caesar had invited blacksmiths from all over Italy caught the attention of officials in the allied cities.
"Wait, Caesar invited all the famous blacksmiths to Rome?"
"I heard he practically holds a monopoly on Rome's engineers already. Is he trying to recruit every smith in Italy now?"
"If all the capable blacksmiths move to Rome, what are we supposed to do?"
"We need to come up with a way to keep them here before it's too late."
Misunderstanding Lucius's intentions, local officials hurried to offer incentives to keep their skilled smiths from leaving.
They offered grants, tax exemptions, and other privileges that local smiths had never received before.
While blacksmiths across Italy unexpectedly benefited from this competition, the men gathered in Rome spent their evenings talking over wine.
"I'll admit, this is far more fun than I expected."
"You can say that again. I feel like a kid playing in the mud again."
After spending their days at the experimental forge, the blacksmiths shared their evening meals in their lodgings.
"Who else would ever tell us to forge whatever we want without worrying about the cost of materials or the time it takes?"
At first, Lucius's proposal had felt utterly foreign.
But as the days passed, all of them became completely engrossed in their experiments.
Some researched new smelting techniques, while others invented entirely new tools.
It was a rare chance to experiment with new ideas without worrying about material costs.
A few even managed to file patent applications in that short time and secure lucrative contracts with Caesar's company.
"Wait, so you forge nails and pickaxes using that method?"
"Yeah, it ensures a much more uniform shape. Plus, it wastes a lot less ore."
The craftsmen had been wary of one another at first, but the atmosphere gradually changed.
Every evening, over cups of wine, they shared the day's successes and exchanged stories from their experiences.
Hoarding secrets was common sense.
But sharing a fraction of that knowledge to gain the respect of peers—and brainstorming new methods together—was equally sensible.
"Why don't you join me at the forge tomorrow so we can test that out?"
"Sounds like a plan."
Over time, artisans with similar interests formed partnerships and began developing new techniques together at the forge.
It was an outcome Lucius hadn't anticipated at all.
＊＊＊
"You want what, exactly?"
"We heard that you sell waterwheels and handle everything from their construction to their installation."
I nodded at the blacksmiths' words.
"Several are already in operation across Rome, and I oversee many of them myself."
"We would like you to build waterwheels for us."
"Well, that's fine by me, but..."
This was an unexpected curveball.
To be perfectly honest, I had been planning to pitch a similar offer to them first.
I had planned to introduce them to the improved smelting methods and facilities, then spread the technology throughout Rome's territories.
And yet, here were the blacksmiths, taking the initiative and commissioning me directly.
"But it will be difficult to install waterwheels at your existing smithies,"
I pointed out. Most smithies were located inside or just outside the city walls.
To utilize a waterwheel, they would have to move their operations near a flowing river.
"A few of us with similar goals have decided to pool our coin and build a brand-new forge together."
"That is... quite remarkable."
A smile crept onto my face without me realizing it. To think that these men, who had eyed each other with such suspicion at first, had grown this close.
I never imagined that gathering them in one place would lead to this kind of synergy.
"Then I would like to make a counter-proposal,"
I said. This was too good an opportunity to let slip away.
"Installing a waterwheel is a massive expense. I will build them for little more than the cost of the materials. Those who cannot pay at once may repay me in installments."
"And what do you want in return?"
The blacksmiths asked, eyeing me suspiciously.
The offer was too generous to take at face value.
"From now on, I want you to prioritize my orders above all others. The amount of work I'll be sending your way is only going to grow."
I told them.
"I will provide you with the standard measuring rod used by my engineers. Whenever you fulfill an order for me, you must follow its markings exactly."
"Is that all?"
"I'll be providing you with even more opportunities in the future."
The demand for iron was only going to skyrocket from here on out.
Not just for new weapons, but for all sorts of farming implements, tools, heavy equipment, and everyday products.
I could have simply expanded the number of forges in and around Rome, but the noise and pollution issues couldn't be ignored.
If I could place large orders directly with smithies and ironworks throughout Italy, that would be more than enough. The resulting competition would push them to improve alongside one another.
"Let's call it an investment in the future."
"We learned a great deal from this opportunity as well,"
One blacksmith noted, the others nodding in agreement.
"And we've made new friends, too. Even after we all return to our respective hometowns, we can continue to exchange letters."
Letters. Come to think of it, with the postal service, they could easily maintain their connections without having to meet in person.
After all, they could freely exchange information. Rome was already transforming into a true republic of letters.
Even if it hadn't been my original intention, I had practically provided a massive networking event for blacksmiths across all of Italy.
"Until now, blacksmiths' collegia have operated only within their own towns or regions. But from now on, we could establish a single collegium for smiths throughout Italy."
One craftsman declared with fervent enthusiasm.
"Which brings us to one last favor we'd like to ask of you, Caesar."
"A favor...?"
"Using this gathering as a starting point, we would like to create regular opportunities for blacksmiths from all over Italy to convene in Rome, discuss our craft, and forge bonds with one another."
"You're talking about a symposion,"
I murmured softly.
In Greek, a symposion was a drinking gathering held after a meal, often filled with conversation, music, games, and debate. The closest Latin term was convivium.
In the 21st century, it had come to mean an academic or scientific conference.
"A gathering where master smiths could exchange knowledge, compare methods, and form connections."
I murmured. If I supported such gatherings, I could spread knowledge from the future throughout Italy far more naturally.
Looking into the eager faces of the master craftsmen, I gave them a broad smile.
"There would be no greater joy for me than to support you in this endeavor."