Saltpeter is really not a matter for Canghuachi, a letter can make his father a large amount of saltpeter, but what he thinks about now is not where the saltpeter is finished, but whether the saltpeter ice-making technology is difficult and whether it can be promoted.

"I'll figure out a way to do the saltpeter thing, you can first tell me how to operate the saltpeter ice making method you said?" Canghuachi put away his past cynicism, and asked Lin Qiya seriously.

Lin Qiya is not stingy, after all, this method is simply too simple, you only need to put saltpeter into the water according to the proportion, as for what this proportion is, you can find out slowly.

And she also said that adding some salt in the right amount would speed up the formation of ice, but salt is expensive now, and she doesn't care about the time saved after waiting for hours.

"It's that simple?" Deng Duoer had been listening, and was very surprised to know that the way was so simple.

"It's that simple, it's just that no one knew about it before, and even if someone knew, they hid it and pinched it, how can I be so generous and tell you directly." Lin Qiya said with a smile.

"The blue-eyed merchant told you again?" Yu Zimo looked at Lin Qianya and smiled happily, but I believe that the other two were curious about how Lin Qianya knew this way.

"That's right." Lin Qiya glanced at Yu Zimo.

"I'd love to meet the blue-eyed businessman you mentioned, and I feel like he knows a lot." Canghuachi has always had an obsession with the blue-eyed businessman that Lin Yuya said, and he even wrote to tell his father that he should also pay attention to such a person.

"This ice-making method, Huachi, you can tell that person, maybe it can be used on the southern border to cool down the soldiers." Yu Zimo didn't want Canghuachi to continue to talk to Lin Qianya about the blue-eyed businessman, so he helped Lin Qianya divert the topic.

"To the soldiers? No, no, this saltpeter ice can't be eaten, and eating it will cause diarrhea, but you can ice things through the container. Lin Qiya panicked when she heard that this was for the soldiers at the border, and she originally planned to secretly cook something cold to eat at home, but now she can only say this method.

"It's okay not to eat it directly, right?" Canghuachi was a little dissatisfied with Lin Qiya just saying this now, but fortunately, Yu Zimo mentioned this, otherwise the border soldiers would have eaten diarrhea, and he and his father would probably suffer.

"Yes, when you make ice, you use a different container to refill the clean water, and you will freeze the clean water when the saltpeter water freezes." Lin Qiya has nothing to keep at this time.

And used a small bowl to re-demonstrate it in front of everyone, so that the three of them, including Jin Zhi and Feng Shi, who had been on the side, knew this method.

When the group went back, they all managed to find some saltpeter for experiments, and with homemade ice, it was not so hot to sleep that night.

Ten days later, Canghua Pond actually found enough saltpeter, and also began to send ice cubes to Lin Qiya's side.

Wei Ding's business has also become very good these days, because there is a large bucket on his ox cart, and this bucket always exudes cool air, so that everyone who rides his ox cart will feel cool.

Yunyue Inn has placed a metal square cabinet in each private room, and the cool air emitted by this cabinet can completely make the whole private room cool, so customers hope to book a private room after coming to feel the coolness.

As the weather gets hotter and hotter, Lin Weiya customizes several metal cabinets with lattices, which can not only be used as Xiaoice boxes, but also cool down the house.

And Feng's, who has been working outdoors, Lin Qiya has also prepared such a metal cabinet here, with iced water inside, Feng's can take a sip to relieve the heat as long as it is hot, which is also regarded as her boss's care for employees.