In the early morning, a breeze blew by.

Qi Tian led a group of people to the port outside the city to receive the metal ore from Xiguan.

These ships are very fast.

People still get tired from walking on the road, and horses also need to rest.

But for Qitian's big steam ship, the most they can do is find a place to add some coal.

There are not too many other problems, and you can run around the clock 12 hours a day.

Ye Ning also came with her, and she was stunned when she saw several large ships.

"Ms. sir, there are so many big ships... How can one of your imperial workshops use up all the materials on them!"

National-level resource scheduling is very large.

The resources of Qitian and others in Xiguan have reached this level.

"Of course it's impossible, so we need to build factories and prepare for steelmaking!"

Qitian wants to help this era move forward.

For this purpose, a steam engine is not enough.

Other aspects must also keep up.

Such as trains.

If you want to lay the rails, you need these materials.

"Building a factory?"

Ye Ning looked at Qi Tian curiously. In the eyes of people of their time, the concept of factory was somewhat difficult to understand.

"It is a factory that can accommodate hundreds or thousands of people working together. It has specially made molds. All the fired liquid metal is poured into the molds, and rails can be made in large quantities."

Qi Tian is not too worried about the foundation of the railway track, because it can be done with cement and some gravel.

The key is mass production of rails.

Ye Ning caught the key point:

"Ms. sir, if there was a mold that could be poured as you mentioned, there would be no need to build a factory, right? There would be too many people."

"Honey, you discovered your blind spot!"

Qi Tian pinched Ye Ning's little face with great satisfaction.

"ah?"

Ye Ning widened her eyes in confusion, waiting for Qi Tian's response.

After hearing this, Qitian said:

"Since it's a factory with so many people, I won't just let them make these things. I also want to make something else."

"What?"

"Make ice!"

This is Qi Tian's own business outside of being entrusted by Emperor Liang.

Summer has arrived, and when he came back this time, Qi Tian had already discovered that the entire capital seemed to be extremely hot.

In order to relieve the heat, some people drink mung bean soup, while others eat large cold watermelons soaked in well water.

But it's no use.

Far less effective than a popsicle.

"Ice cubes? That's something only available in winter..."

Even Ye Ning, who comes from a distinguished family, cannot touch ice in this weather.

Most of the ice cubes that appeared at this time were ice cellars exclusively used by the royal family.

In hot weather, some ice cubes would be prepared and sent to Emperor Liang's palace.

But the reserves are pitifully small.

From a certain perspective, ice cubes are truly rare objects in the summer of this era.

"No, no, it can be made."

Qi Tian smiled and waved his hand.

They are about to cast the mold now, and they will also make the mold for making ice cubes later.

You can start making ice using the saltpeter ice making method.

"Really? Then we are not afraid of the heat in summer?"

Ye Ning's eyes widened in excitement.

Qitian's method can be called a miracle in this era!

"certainly."

He arranged for someone to transport the things to an open space he bought outside the city.

Qi Tian erected a greenhouse here, and then began to lead people to build it.

Xiao Yan, who was working in front of the emperor, also came to Qitian early.

"Master Qi, are you looking for me?"

"Xiao Yan, you recently helped me make some molds that can be used when pouring liquid metal."

Qitian informed Xiao Yan of all the dimensions of the railway tracks.

"No problem, is there anything else?"

Xiao Yan nodded, wrote everything down on the paper, and then continued to ask questions.

Qitian thought for a moment and then said:

"I'm making some grids three inches long and wide, and using an iron plate to put them all on top."

What Qi Tian asked him for was a mold for making ice cubes.

Several boxes are connected to an iron plate, and a sink is placed underneath.

When making ice cubes, fill these connected iron boxes with water and put them all into the sink.

Then add some saltpeter to the water tank.

Saltpeter can absorb heat when dissolved in water.

Eventually, all the water in these iron boxes will turn into ice cubes.

"Let's do this...this is quite simple. I can give it to you in the evening."

Xiao Yan nodded.

The mold requires precision, and more needs to be made so that they can cast rails in batches.

But what Qitian needs to make ice does not need to be so precise.

"Okay, go ahead."

Watching him leave, Ye Ning looked at the two hundred kilograms of saltpeter that had been moved in the distance and said:

"Ms. sir, shall I buy some saltpeter for you and bring it back?"

"That's enough."

Qi Tian was stunned for a moment, and then remembered that he still had some things that he had not told Ye Ning.

"Enough?"

Ye Ning was puzzled.

Since Qi Tian said that saltpeter is needed to make ice, why is only this small amount enough?

"Silly girl, these things are just like salt. Use them once, and they can be used again after they evaporate and crystallize."

"Wow! My husband, no wonder you said our popsicles and ice cubes are sold very cheaply!"

With Qitian's method, the loss is very small.

After recycling, the cost is reduced, and the final products sold are naturally less expensive.

"If you want to buy some, go buy some watermelons that are in season. When we come back, we'll cut them up and make watermelon popsicles!"

"What is Popsicle?"

Once she and Qi Tian are doing things together outside, Ye Ning behaves more like a child who likes to ask questions.

"You can freeze watermelon juice into ice and eat it, or you can make a smoothie."

"hiss!"

At this time, not only Ye Ning, but also a group of workers who were doing construction work around them took a deep breath.
To be continued...