Around the time Alexander and his students were about to leave, Billy finally solved the last mystery of the cart. To make the potency start to appear, he had to change the aerodynamics of the vehicle in a way that it would do better against the wind. Since the engine wasn't big and didn't have to be on the front of the vehicle, Billy made the front of the cart to have a triangular shape. He even put windshields in front of it. Making glass was just that easy for him now.
This might be hard to believe, but glass is made from liquid sand. More specifically, glass is made by heating ordinary sand, mostly composed of silicon dioxide, until it melts and turns into a liquid. You may wonder why the same thing doesn't happen on hot days at the beach. Still, the answer to that is quite simple: the melting temperature that the sand needs is very high, around 1700° Celsius.
When the molten sand is allowed to cool, it doesn't return back to its gritty yellow state that you began with. The heating causes it to undergo a complete chemical transformation, thus attaining a new inner structure. Regardless of the technique employed for cooling the molten sand, it never quite sets into a quintessential solid. Instead, it turns into a frozen liquid or, what a material science graduate would like to call, an amorphous solid. Basically, glass is more like a cross between a solid and a liquid, featuring some crystalline structures generally found in solids, as well as some molecular randomness is often seen in liquids.
"I googled it a long time ago when I got curious, but I wonder how I still remember the exact words…" Billy frowned. "Nevertheless, this isn't so bad, If I do say so myself."
Magic Cart Lv 00
Potency: 03
Movement Speed: 05 meters per second.
Mana Capacity: 0/100
Durability: 10/10
The potency status determined how much the vehicle could work with a single point of mana and stamina, so it could move quite a lot, around fifteen meters at its current level. Still, Billy felt that there was some room for improvement, so he didn't want to level up that yet. Besides, the tunnels still have a long way to go.
"I don't know if I will manage, but I ever wanted to make a magic copy of an airplane, then the potency of my creations will need a lot of improvement," Billy nodded to himself.
"Couldn't you sell those and help people harvest more and faster?" Alexander asked.
"I could, but it isn't like I need more money than I am earning, not to mention, it isn't like the allied states are having a hard time with that issue," Billy explained. "I want to keep this as a secret to give us some advantage in the future."
"I see… That is why those tunnels are so lengthy," Alexander said. "Anyway, I will look forward to your final product. we will be going, so it will take a while for us to meet again."
"Keep your guard up," Billy said. "You are too relaxed around those kids."
"I know, I know," Alexander said.
Over the last two weeks, some of Alexander's students managed to master the second version of Light Spear, but even so, doing just once was just too much for their bodies. Billy also managed to do that, and ten times was his limit. Still, it would come in handy when he decides to clear the dungeons since only bosses had that much defense to withstand the usual Light Spear.
On the schedule, Sarah and her students showed up the next day after Alexander's departure. While she looked fine, her students looked exhausted, like they hadn't slept for days… Billy never saw her lessons, but it looked like she was a bit harsh with her students, or maybe they were just eager to improve. They didn't seem that unsatisfied or angry, after all.
Unlike the others, Sarah wasn't that talkative, so she kept her distance while her students were fighting in the dungeons. He assumed that was the normal way of acting for a married man. Lily was a bit oblivious, so she didn't consider that. Actually, she couldn't care less about such things.
In any case, when Billy checked their levels and the levels of their skills, he confirmed that her students were a few levels above the others. Thanks to that, they managed to stay inside the dungeon for two hours even on their first day.
"Billy, I learned that," Sarah suddenly declared.
After saying that, Sarah created a small spark of lightning above her hand. Billy already expected that she would be the first to learn it, but her control was quite something. The small lightning bolt almost flew upward in a straight line.
"You must have trained hard to control it that well," Billy said and tried to do the same.
In the end, his lightning bolt zigzagged in the air, but the last point still was in a straight line above his hand. Billy couldn't control that yet due to the sheer power of the magic. While that helped him in making the target panic, since it was so fast, few people could see the path of the bolt. Regardless, Billy hadn't learned her ice spell yet, even though he had tried a few times. It seemed that one needed sharp senses as well. He probably could do that with Earth magic, but it was a lot slower since Earth is more dense than water and ice. So, distant enemies would have an easy time noticing and moving away from the traps.
"Putting that aside, some peddlers visited the town that I am managing, and they were brave enough to do business in Neles territory," Sarah said.. "Thanks to that, I heard some disturbing news… The two commanders of their army were executed, and their heads hang at the entrance of a castle."
