The Mechanical Era

Samuel and Victor overlook the large stone building with a wooden roof. The open wooden windows, which allowed anyone to take a peak at what went inside, was protected by iron bars preventing anyone to enter through there.

The only way inside was through the front door guarded by tall muscular elite knights holding pointy spears. It was clear that the prince had already arrived. After taking a deep breath, they walked right up to the knights, and requested to enter the building.

"Letter?" asked the knight on the left. Victor takes out a small piece of white paper and hands it over. The knight carefully inspects it while the other keeps an eye on the two.

"All clear. You may enter." he said. Before Samuel could enter, he asked the knight a question.

"Were we late?" he asked.

"No. Sire had just arrived earlier than scheduled. New security protocol." he said. Satisfied with his answer, Samuel thanked the man and went inside. There, they walked down the hallway, and to the lab room.

Though the craftsman seem to be present, Kant was nowhere to be found. Samuel asked one of them where he was.

"He is in the testing room, building something with a few craftsman." one said.

"He told us to sit down and wait until he comes back." said another. The twins took their word from them, and decided to sit down. The two didn't have to wait long till he came back in his while tunic and black breeches.

"Welcome back everyone. I am glad you all made it to conduct a new test. Now before we move on, I need to make sure that everyone is present." he said. On the table, he picked up a blue file and opened it.

Kant started to call out the names, like a teacher in his classroom. The craftsman, who were all sitting, got up one by one and answered Kant with 'Present!'. After a few minutes, he closed the file and places it in a drawer.

"Alright. It appears that everyone had made it in time. We shall now begin." he said.

"Now as you all know, a steam engine uses pressure to move a piston inside of a cylinder, allowing it to move. Yesterday, we made what is called a single cylinder steam engine.

However, there are many limitations of a single cylinder engine. First of all, a huge and robust cylinder is required to with stand and accommodates high pressure steam. The second is the condensation loss.

Because of the large pressure difference between the inlet and exhaust conditions, there will be large temperature difference and which results in a lot of condensation losses." He remained silent at first.

"This... is where a multiple-expansion engine comes into play." he finally said. Kant took a piece of chalk from the wooden cup and started to draw on the black board.

He drew one large box. He then separated the box into two parts; one on the top, and the other bottom. The new top box was much smaller than the bottom. It was about 1/3 of the entire box itself.

Kant continued to divide the boxes once more. On the top box, he separated it into three unequal parts. The first box was about 1/4 of the top box. The second one was a bit larger, while the rest went to the third box.

On the bottom, he did the same. However, he went to divide the bottom even further. On the first box on the left, he divided them in half. The middle box had it separated unequally, with the left gaining only 1/4 of the size. Same went for the largest box. Only then, he started to draw the components.

On the right side of the boxes, he drew the pistons. The top boxes had the piston head with a bit of the piston rod, while the bottom had only the piston rod attached to a connecting rod, which itself was joined with the crankshaft, represented by a line near the bottom of the lower box.

On the left side of the mini-boxes, he drew the valve rods mainly situated on the left mini-boxes on the lower box. He then drew the intake on the left and the exhaust port on the right, with a with two pipes that allow steam to go in between.

He places the chalk back in the cap and face the craftsman sitting on their chairs, silently waiting for Kant to deliver his explanation.

"This is a concept for a multiple-expansion engine. As you can see, this engine has more pistons than a regular single cylinder. Though this is not the exact version we will be working with, I deem it good enough.

A multiple-expansion engine is a more advanced steam engine expanded to contain more stages to increase efficiency and horsepower with the additional use of cylinders and progressively lower pressure to extract as much energy from the steam. " he said. Kant then first points to the intake placed on the top left of the diagram.

"This is where high pressure steam enters. It pushes the piston downwards, causing it to spin the crankshaft. This causes the valve rod to move and thereby allowing the steam to flow to the next cylinder.

This process occurs all over in the next cylinder and is finally released through the exhausted. However remember, as the pressure decreases as it moves on to the next piston, it needs a larger area to make it more effective. Which is why I separated the boxes unevenly.

This causes the crankshaft to move, which is connected to the flywheel. Since this model theoretically gives out more power, he should be able to expect more revolutions per minute from it. Though we need to conduct test to prove it." he said.

Kant then turned to the craftsman. "Any questions?" he asks. They all remain silent. Kant takes that as a negative.

"Alright then, let's head to the testing room." he said.