The next few days were exhilarating, to say the least. In the coming days, I was about to spend all my time in Kraus's forge, surrounded by his team, including Merlin, as we prepared to work on one single item. We are ready to build the first dynamo, which is probably a unique achievement worldwide. A few days ago, my people finally brought back everything I needed, including sufficient copper to start.

"This will do good!" Merlin added with a moan, stretching, wearing a blacksmith's apron, ready to work. "I am totally stuck with this wave thingy; I just can't seem to get it... Although I am pretty sure that flying ship the Empire had done the same thing when I felt that funny feeling. It is fun to be able to think about something else!"

"How many problems swirl in your head anyway?" I asked back, grinning, making him think, tilting his head.

"Only a few. What I call problems are things that I can't understand; issues that can be solved quickly are not problems!"

"Minister Merlin is a unique individual."

"He is, my Forgemaster, he is! Anyway, let's get to work! First, let's start with the frame of our little magic box. We'll forge a sturdy iron skeleton to hold all the components together. It must be solid and well-balanced to handle the rotational forces without warping or bending. If it is too weak, after turning it on, the whole thing will twist into nothing but a paperweight, so I expect everyone to live up to the name of your Forgemaster!"

I don't know if my quick speech scared or motivated them, but it wasn't a lie. I did not want to waste any copper we got our hands on, even if I could melt it down afterward. Maybe my warning was unnecessary, or perhaps it made the end product testify to the skill of my blacksmiths. Even though it took three days to complete it, I was more than happy to be slow and thorough.

The frame, made from sturdy iron bars meticulously forged and welded together, stood 1.5 meters tall and a meter wide. It constituted the backbone of my dynamo. Its structure was robust and unyielding, designed to withstand the forces generated by the future spinning rotor within. Looking at it, silently thinking, I felt confident that we did not make any mistakes and it wouldn't bend.

"It would have been even better if Lady Sasha could help!" Kraus sighed, lamenting while touching the bars, which bore the marks of their hammers, its surface being rugged and textured. "With her abilities, we could have melded them together seamlessly."

"You, just like me, are easily used to her magic, eh?" I grinned, patting his shoulders, "It is fine!"

"I could have used magic..." Merling grumbled, but I only looked at him with a smile, knowing that he probably would have amplified the strength of the furnaces, melting the whole thing down into a clump of iron. Nobody came close to my wife if it was about manipulating the flames and the heat.

"As the heart of the dynamo, the iron frame will provide the stable foundation I need. It will hold the coils of copper wire in place, securing them firmly to maximize their efficiency while supporting the rotor's spinning shaft, ensuring smooth and precise movement with minimal friction. So... what we should move onto next are the copper wires."

As my head turned, landing on the gathered materials, by rough estimation, we had enough to build two dynamos. So, even if the first one fails, we can still redo everything.

"Take the copper and start melting it down! We are going to make wires out of it until I say so! Then, we will wind it around a cylindrical form to create coils, following the blueprints I made. Make sure that you measure everything and do it to my parameters. This is important, guys! The more coils we have, the stronger the electrical current we'll get... but I also want to stay moderate for the first prototype. We'll then mount these coils onto the frame circularly, leaving space in the middle for the rotor, so... let's continue!"

Once again, this process took us two days, and in the middle of it, Sasha came down to visit with my mother and Luna, looking over our work and sighing continuously. I knew she was feeling left out, wanting to be part of the project, making it with her two hands, touching and shaping molten iron as if it were sand.

"Let's go.... please?" Luna groaned, pulling on Sasha's clothes, "I'm melting here! We are having our piano lessons soon with Mikan anyway!"

"Go." I whispered, kissing her forehead and smudging her face with my dirty hands, "The longer you stay, the angrier my mom will get~!"

"I'm right here, son, you know that?"

"Ehehehe..."

In the end, Luna had to drag her out as she watched us make the coils, ensuring they followed my exact measurements. If something didn't fit, we had to melt it back down and reforge it. But... that was not the challenging part. It was what came next: the heart of the dynamo—the rotor.

When the day came to start building the main piece, I was a bit nervous as we were missing one of the main components: magnets. I made sure that our caravans kept a lookout for lodestones because of it. After detailing their properties and appearance, they managed to bring back some, but not enough for me to be confident. While most of the guys were building the rotor, following my instructions and plans, I was with Merlin and Kraus, personally trying to create the magnets for the finished product.

A case of content theft: this narrative is not rightfully on Amazon; if you spot it, report the violation.

"So this a lodestone... I still don't feel anything from it, unlike from CC." Merlin hummed, looking at the big chunk of rock.

"Here, let me show you!" I answered with a happy laugh, bringing over some iron shavings. When I moved the lodestone above it, I saw their amazement as the shavings reacted to the natural magnetic field emanating from it. I let them play around a little, sticking different things at it while I let them experiment to their heart's content.

"Why aren't we using this?" Merlin asked, looking at me after playing for long enough.

"I don't know if it would be sufficient, and I don't want to use it up and then be left without anything if we fail. So, we will try our hand at magnetizing some iron rods!"

"Magnifying?" Merlin and Kraus asked, looking at each other before I repeated the word.

"You'll see. My hope is that it will be good enough for us to make it work. If our first prototype can function, the electricity it creates can then be used to develop stronger magnets. From then on, we can continue to refine and mass-produce it."

"So... magnetism creates electricity? And electricity creates... magnetism?" Merlin asked, scratching his chin, thinking about it.

"I will write a book about it later, but there is also something called electromagnetism. It is not as simple as you think. Anyway, that would be a very long discussion right now!"

"Okie-dokie! Uuuu, I can't wait! This is fun! I want to know more!"

"Okay, first, let's shape this bad boy into the form we need."

The rotor was created quickly as we were already in a pretty good rhythm, working together, but it was nothing but a regular iron when it was finished. We still needed to magnetize it, which was the tricky part.

"First, it will need a heat treatment," I explained slowly, looking at the two. "We will heat it to a high temperature until it becomes red-hot, which we will call annealing. It helps to align the material's internal crystalline structure, making it more receptive to magnetization. Once the iron is heated, we will rub it vigorously with the lodestone in a consistent direction. Don't mix this up! It must be done in a uniform order! This motion is what aligns the magnetic domains within the material, inducing magnetism."

"We would really need Sasha for this," Merling whispered, and I couldn't help but agree. She could hold the red-hot metal barehanded, but... here we are. Life can't always be easy.

"Do we cool it down after?" Kraus asked, making me shake my head.

"We will allow the iron to cool slowly while still maintaining its magnetized state. This helps to set the magnetism within itself and make it permanent. If we dump it into the water, it will screw things up. This is not something that can be rushed, so I need everyone's full focus. Got it?"

"Yes, My Lord!" They answered in unison, and we finally began, making my heart race...

...

....

......

Multiple days later, the fully assembled and completed dynamo was ready for its first live testing within the workshop. This time, Sasha was there from start to finish, asking us a million questions. Merlin was happy to answer all of them as he held the first draft of my recollections about electromagnetism. I think I once saw him sleep with it...

"For now, it will be cranked by hand, but if it works, we can attach it to a water wheel!" he exclaimed happily as if he had built it by himself.

"He has infinite energy, huh?" My mom whispered, walking up to me, and I couldn't help but nod. Unlike Merlin, who was bouncing around, Kraus was standing there, examining the dynamo one last time, his eyes encircled by tired, black bags. I wasn't much different either, as our previous few days consisted of nothing else but work... it was like being back in the army for me. And I liked it. When Kraus straightened his back, it was the signal for me that everything was ready for us to fire it up.

"Okay, everyone! Time to see if this one was worth the work or not!" I laughed with a clap, silencing the tiny crowd, nodding at Kraus to start cranking it.

First, he went slowly, ensuring every component was moving correctly and not hitting something before finally speeding up. To make sure the dynamo wouldn't flip or something, it was bolted down to the ground, and my gaze was fixated on the charred cotton thread filament we attached to its output.

"Is it working?" Sasha asked, looking at me while I continued staring unblinkingly as I answered.

"When an electric current passes through a charred cotton thread, it heats up due to its resistance to the flow of electricity. This heating effect is known as Joule heating, and it increases the thread's temperature. As the temperature rises, it emits visible light through incandescence."

"Through... what?" She murmured, and it was Merlin who answered her happily, knowing about it after reading my quick notes.

"Incandescence is the emission of light from a heated object, and it occurs when the object's temperature is high enough to cause it to glow!

Charred cotton thread, being a carbonized material, is highly resistant to electricity and can withstand the heat generated by the electric current without burning up. Hehe, I suggested it because Leon was thinking about things called tungsten and other funny-named metals!"

"You mentioned why not use a wick." I corrected him with a slight smile. "From that, I remembered this method."

"It's the same... Almost..." He mumbled, looking a bit dejected.

"Long story short," I continued, already happy because I heard the unmistakable sound of electricity buzzing. "When it finally heats up and produces light, we will know that a current is passing through it. Which means it is working!"

"It does!" Sasha exclaimed because, true enough, the moment I finished speaking, the thread began glowing, producing light, undeniably showing that we didn't build a useless thing.

I couldn't help but let out a soft sigh, finally calming down. Nodding towards Kraus, I signaled him to stop. I could see that he felt just as relieved as I was, realizing that it was indeed a great success! All things considered, I just witnessed the very first, very primitive lightbulb work—well, kinda. The principle behind it was the same. Would this mean we can start replacing candles with lamps? Probably not. But one day... in the future. Right now, I was glad and happy enough that I had something that could produce a direct current. It was the first time human hands had generated electricity in this world. What remained next was streamlining it and smoothening out its workings. Then... we can start thinking of practical applications and upscaling them.

Reading Kustov's letter made me realize I need to mix my knowledge and create a hybrid approach to my future machines. If I only focus on one part, I would make it vulnerable. Enough one anti-magic spell and even my biggest war machine would become useless. If I focus only on machinery, I will never get to a level that will enable me to build them in my lifetime. But if I mix the two, we will be in business in no time!