"What is this?" asked the nightingale, looking at the shiny black stone on the table.

"Obsidian. Roland didn't lift his head, concentrating on drawing the drawings in his hand.

"Black ...... What stone?"

"No, I'm talking nonsense. He sighed, just looking at the shape and color, who knows what kind of stone it was. He is not a student of geological exploration, and pure metals may not be able to distinguish them in front of him, let alone ores. The only bit of knowledge in his head is telling him that most of the ores are complex compounds, and the impurities are different in different colors, just take iron ore as an example, hematite, pyrite, and siderite are completely different from each other in terms of appearance, especially pyrite, which sometimes shows a light yellow metallic luster, and is often mistaken for gold, so it is also nicknamed Fool's Gold.

As for high temperature resistance...... There is no fixed melting point of the compound itself, and it is also related to impurities and composition, and its varieties cannot be distinguished by temperature alone. Moreover, the metal elements exist in an ionic state, and the purification method is not known, and it is useless to burn them.

"Is there something you don't know?" said Nightingale in surprise.

"What's more," Roland put down the quill and made himself a cup of black tea, "do you want to drink it?"

"No," she waved her hand, "yes, beef jerky isn't as tasty as grilled fish fillets, so you'll have fish fillets in your drawer in the future." ”

"......" Roland was silent for a moment, deciding to act as if he hadn't heard it. He also planned to throw the stone to the chief alchemist Kemo Stowler to dispose of, the mineral was more or less radioactive, and it was not a good choice to use as an ornament in the office.

Recently, after Zoroya's abilities evolved, he found that he could suddenly make a lot more.

The first is the piped water system, which is something that greatly improves the well-being of residents. Think about it, it must have been terrible to come home sweaty after a busy day and try to wash your slimy body, only to find that the water tank was empty and you had to go to a nearby well to fetch water. Moreover, Roland was also tired of scooping water from the tank to wash his face and hands, he always felt that the water in the tank for a few days could grow parasites, not to mention that the water tank was rarely cleaned once a month, and if you looked closely, you could see the scale deposited at the bottom of the tank fluttering like a caterpillar.

If the water tower is used for water supply, there is no technical difficulty - the water from the Chishui River is pumped into the water tower by using a steam engine, and then flowing into each household along the pipe by the siphon principle, forming an automatic water supply system. The reasons why Roland has not been implemented are...... Material.

The water supply pipe is either iron or copper, and if the iron pipe is not treated with anti-rust, it will have to be scrapped after a few years. Copper pipes are perfect water supply pipes, corrosion-resistant, non-scaling on the inner wall, non-toxic, and even copper ions have a sterilizing effect, but the output of the North Slope mine is far from being extravagant to this extent, even in later generations, copper water pipes are something that high-end residences will consider.

At present, border towns are not only unable to export minerals, but even have to import metal ingots. Therefore, whether it is iron or copper pipes, Roland is reluctant to use them to build a water supply system that cannot be profitable, but purely for enjoyment.

But now it's different, with Zoroya's coating, it means that he can use his white gloves to produce water pipes with magic alone - for example, take an iron pipe as a mold, wrap it with paper, and then let Zoroya cover it with a coating, and pull out the mold to become a pipe. Even if such a pipe is not compression-resistant, it can be placed in a ditch with a cover.

The second is the power supply system...... I'm afraid that this will not be able to spread to the whole town in a short time, but it has always been what Roland wants to achieve to make the castle full of light, reading with a weak candle flame is too painful, and it is very harmful to the eyes, plus summer is coming, what is it like to have torches and candles full of torches and candles on a sultry night?

Now with generators and electrical wiring, it doesn't seem so far off for the castle to enter the electrical age early. As for the filament of the bulb...... He vaguely remembers that before the use of tungsten filament, people commonly used carbonized bamboo wire to make incandescent lamps. Bamboo is not a rarity, it can be found in the woodlands south of the Chishui River.

However, what the border towns need most at present is iron-smelting facilities. The production of iron is directly related to the scale of machinery production and weapons manufacturing, and is also the foundation of the town's survival.

"This is what you painted...... A tower?" asked the nightingale, sitting at the table, curious.

"Almost," Roland nodded, "but it's empty, and it's used to fill fuel and ore, and it acts like a shaft furnace, smelting iron ore into pig iron." ”

This is the blast furnace, an upgraded version of the ancient shaft furnace.

He had visited the construction site to see the shaft furnace designed and manufactured by Losia, and to be honest, in addition to the small capacity and low furnace temperature, the structure of this furnace was already very close to that of the blast furnace, and if it weren't for the evolution of Zoroya that gave the town the ability to produce refractory bricks, he would have planned to build a dozen more such shaft furnaces.

But with refractory bricks, it is natural to consider blast furnaces with higher furnace temperature and larger output.

The height of the newly designed blast furnace is nearly eight meters, which is four times that of a shaft furnace, and the furnace body is in the shape of a tower, with an inner diameter of three meters at the maximum, and a support frame is erected at the bottom to prevent collapse. The walls of the furnace are thin and thick, with a thickness of up to half a meter at the belly, and the innermost layer is made of fireproof bricks coated with Soloya, and there is a circle of air supply vents into which air is pumped by a steam engine.

In order to make the most of the power of the steam engine, Roland DG also designed an automatic feeding system for the blast furnace, consisting of a climbing rail and a special feeding car with a movable door at the bottom. After the trolley climbs to the top of the furnace under the traction of the steam engine, the buckle at the bottom of the car is hooked in, which opens the pouring port and dumps fuel or ore into the furnace. For this era, the system is state-of-the-art.

Unlike shaft furnaces with large openings and low heat, blast furnaces, once in production, do not stop operating for a long time, and must be continuously fed in fuel and ore, and the output is much higher than that of shaft furnaces. With the construction of five or six of these blast furnaces, the town's pig iron production would be multiplied.

......

Drawing all the drawings, Roland rubbed his somewhat numb wrist, took out a box from under the table, and pushed it in front of her.

Nightingale was stunned, "Is this ......?"

"Hmm...... I was going to give it to you earlier, but it took me some time to carve the pattern, after all, I wasn't too skilled in using the machines in the factory," Roland smiled, "Let's open it and take a look." ”

She reached out to open the box and let out an exclamation.

There were two revolvers staggered to the left and right - unlike the prototype guns used on the day of Carter's competition, these two pistols were shining silver, the surface was shiny enough to reflect a human figure, the grip and body were delicately engraved, and the barrel was stamped with the name of the nightingale: "To Veronica".

This plan has been brewing in Roland's head for a long time. Compared with the front-loading flintlock pistol, which is inconvenient to carry and troublesome to use, the newly developed revolver has been quite perfect, and both safety and firing rate have been maintained at a high level. A witch like Nightingale, who is extremely mobile, is looking forward to what kind of power a gun can exert in her hands.

"Thanks," she smiled as she picked up the two pistols and jumped off the table in a firing gesture, "will you teach me how to use them?"

"Of course," Roland nodded, and the other party's white piercing customer service and dazzling smile made him instantly understand what it means to be handsome and have no friends, "It's not difficult, just sneak into the target, pull the trigger, and shout that noon has arrived." (To be continued.) )