"Come, try to put these two iron plates together," Roland said.

Anna stretched out her finger and pressed it against the seam of the iron plate. Flames erupt from between the fingers, melting at the interface at a rate visible to the naked eye.

"Reduce the firepower and do it again on the back. ”

She nodded and did so. The two iron plates are spliced at 90 degrees and are firmly welded together.

Roland examined the lower joints and found that the result was just as he had imagined it to be—a perfect weld without any blemishes. If you polish it a little and the fluid traces of the molten iron are removed, the two iron plates are almost indistinguishable from the forging body formed at one time.

"Very well, Miss Anna, it is simply wonderful," Roland could not help but admire, "and then we will join the other two iron plates as well." ”

"What is this? a ...... made of iron? Buckets?"

"No, it's a cylinder," he corrected.

"Cylinder?" Anna repeated confusedly.

"Yes, it can be used to fill the air," Roland said, pointing to another square iron plate, "see the little hole in it? The air enters the cylinder through this little hole and pushes the piston - well, the piston is an iron plate that is a little smaller than the inner diameter of the cylinder, and it moves freely in the cylinder. ”

Even Anna was dizzy in front of so many words, "What about these...... Cylinders, pistons, whatever, what's it for?"

"To make a machine that moves automatically. ”

The steam engine brought the driving force needed for the first industrial revolution of mankind and completely liberated human and animal power.

Its schematic is familiar to every mechanical dog, and to put it simply, it is an enlarged version of a boiling kettle. The boiling steam is directed into the cylinder, which pushes the piston and connecting rod to convert the thermal energy into mechanical energy.

The principle is exceptionally simple, but that doesn't mean it's easy to make. The difficulty lies in the tightness of the cylinder and the piston, as well as in the manufacture of the gas pipe. When the skills of metalworking are not enough, it is impossible to make a qualified cylinder by hand forging.

However, Anna's ability perfectly compensates for the lack of craftsmanship.

Roland only needs to design four iron plates of the same size in advance, let the blacksmith shop cast and polish them, and then use right-angled plates to fix the shape, and then Anna welds them, to get a square cylinder with extremely high rigidity. With the help of the witch, he didn't have to build a barrel boring machine and then machine a round cylinder, as is the case with the traditional process. The same is true for other large parts, which can be made into small pieces and then spliced together, so that even a small workshop such as a blacksmith can work together to make all the parts needed for a steam engine.

In fact, before the invention of welding, people could only rely on bolts or riveting to join small parts, and the inside of the cylinder had to be smooth, which was obviously not possible with conventional connections.

The only trouble is the gas pipe. There is nothing special about its production method, a long iron plate is burned until it is red-hot, and then put it into a grooved mold, and hammered with a hammer until it is formed, which is also the method of making the barrel of a front-loading flintlock pistol. It's just that the barrel also needs to be straightened afterwards, rifled and so on, which is more complicated.

The trouble with it was that Roland couldn't call the blacksmith to his back garden, the witch couldn't be exposed for the time being, and striking iron was really not his forte. In desperation, he had no choice but to let the chief knight do the work for him, and he commanded by the side.

After three days of tossing and turning, Roland finally put together the first steam engine in the backyard.

"Is this your mighty thing?" Carter frowned as he looked at the strange machine, first sure it had nothing to do with cult rituals. He had put on every lump of iron with his own hands, and it looked like a sealed furnace. If the devil could be attracted to it, it would be too counterintuitive.

But how do you move a bunch of iron lumps? It looks clumsy, and it has no legs, so can it fly?

But in Roland's eyes, this seemingly rudimentary machine exudes industrial beauty. Standing on the shoulders of giants, he naturally did not follow the route of the Newcomen steam engine, the Watt steam engine, and the improved steam engine, and his first prototype was a high-pressure steam engine with a double link and a sliding valve. Its production is not much more difficult than the most primitive steam engine, and the key lies in some innovations in ideas.

"You'll find out later. ”

Roland poured buckets of water into the steam room and told Anna to light the firewood.

Ten minutes later, the water was boiled and rumbling and tumbling. Soon, there was a crackling sound in the cylinder, which Roland knew was the sound of the cylinder expanding as it was heated. The iron plate of the piston is thinner, and the expansion deformation is larger than that of the cylinder block, and it will eventually be firmly pressed against the cylinder wall.

"Isn't this boiling water? I didn't expect it to be a stove," Carter muttered.

When the cylinder was filled with steam, a scene that made Roland very excited appeared. The piston begins to push the connecting rod outward, and when the motion reaches the apex, another connecting rod pulls the slide valve, and the steam pushes the piston inward. The two connecting rods spun rapidly with the wheels back and forth, and as the firepower increased, the speed soon reached its peak.

The machine let out a piercing roar, and the exhaust port snorted white gas, and there was an unstoppable momentum.

"That's what you're talking about...... The power that lurks in nature?" asked Anna, dumbfounded.

The Chief Knight's face was full of disbelief, the last of the great iron wheels he had put on with great effort, and now it was spinning like a feather, and he could even feel the air currents stirred up by the wheels when he stood next to him—which only showed that the strength of the iron pimple in front of him was astonishingly great.

A hint of uneasiness gradually rose in his heart.

His Highness said that it could replace human and animal power, and if it was not to lie to himself, when it replaced horses to pull chariots, this brute force alone would be difficult for even ten knights to resist.

It takes fifteen years to train a qualified knight, but it only takes three days to build such an iron furnace. Including the time it took the blacksmith to build the parts, it was only a week.

It does not need to be fed, it is not afraid of cold and hunger, nor is it afraid of arrows and knives. As long as the front is equipped with ramming angles, it can rampage through the battlefield.

So...... Is it still necessary for traditional knights to exist?

In the evening, when Roland returned to his bedroom, he saw the nightingale again.

She didn't wear a hood this time, and sat at the table with a smile on her face, fiddling with a few pieces of parchment in her hand, "It seems that the rumors outside really can't be believed." It is said that the fourth prince is unlearned and has a bad personality, but in fact, he is not much better than the palace master. This is the drawing on the paper of the iron stove? You call it ...... Steam engine, right?"

I'll go, can I still leave some privacy, come and go if I want, you think this is your home!" Roland was full of slander in his heart, and replied with a casual face, "It's a blueprint, but without Anna's help, it's just a drawing." ”

"What can it do?"

"A lot, transporting ore, drainage, smelting iron, forging, wherever you need to make a lot of effort, it can work. ”

"Then I'll take it," Nightingale rolled up the parchment and put it in her robe, "and there are people in the Aid Society who can control the flames. ”

"Hey—"

She waved her hand to stop Roland's protest, "Of course, I'm not taking your stuff for nothing, you can take a look at this first." She placed a small ball of white on the table.

Roland walked over and pinched it with his fingers, revealing that it was actually a roll of note.

He unfolded it lightly and glanced twice, "This is ......"

"The secret letter of the carrier pigeon," said Nightingale in a playful tone, "the recipient is your lady-in-waiting, Tsk, it seems that your harem is not stable." ”

"I haven't touched her," Roland frowned.

Tyr, in my memory, this woman seems to have followed her very early, and the fourth prince was originally interested in her, but he couldn't succeed in harassing her several times. This time, when she came to the border town, she was simply promoted to the head maid and served her closely, and her room was arranged next door. I didn't expect it to be the eyeliner arranged by Brother Wang and Sister Wang?

Although the letter was not signed, judging from the content, nine times out of ten it was written by those brothers and sisters. The letter said that the last failure made the master very displeased, and the next time he took advantage of the riot in the Changge Fortress, he would never be allowed to fail again. Well, you've made it, he thought, or he wouldn't be Roland Wimbledon.

It is unlikely that the letter was forged by Nightingale, since only those involved in this conspiracy would have been clear about the plans for the first assassination. And if the nightingale wants to kill herself, there is no need to be so troublesome.

"You stole it from her?"

"Your chief maid is not so stupid, she is going to burn it after reading it. It's just a pity that I happened to be behind her back when she watched," she gestured, "So, what are you going to do? Do you need my help to "deal with"?"

Roland naturally understood what she meant by the treatment, and after hesitating for a moment, he finally nodded, "I'm sorry for you." He really didn't have the confidence to do this kind of thing on his own, "if he could...... Ask me who is behind her. ”

"As you wish, Your Highness," the nightingale smiled and bowed, "then, this scroll of drawings is the reward." ”