353 Try It
As for the evaporation crystallization method, it was naturally a method of obtaining saltpeter after it was dissolved in water and then boiled or dried.
Jiang Yue also mentioned the temperature-lowering crystallization method. It was said that the dissolution of saltpeter in water would decrease as the temperature of the water decreased. In the end, the dissolution would be so small that crystals would be produced, which would produce saltpeter.
Since it was frozen, the temperature must be very low. Even if the soluble saltpeter was not completely separated, most of it would be seen on the surface of the ice. At that time, he could directly scrape off the saltpeter crystals from the surface of the ice and reuse them.
As for the small amount of saltpeter that was still in the ice, it could be obtained after the ice had melted, boiled, or dried.
However, in order to prevent Sifu from confusion, he simplified everything. As long as Sifu knew that saltpeter could be reused, it would be fine. As for other things, when the ice froze, there would be saltpeter crystals would be produced, and Sifu would naturally know how to spot them.
At that time, Sifu would at most think that his guess was wrong in some places, and he had never touched saltpeter before, so it would only be reasonable if his guess was wrong.
If he guessed everything correctly, with Yifu’s shrewdness, he would definitely notice that something was wrong.
“Can it really be reused?!” Xue Sifu rubbed his hands together and his eyes brightened. He felt that this was going to be a great business opportunity. “That’ll be even better! Then we would only need to buy saltpeter once! Quick, quick, quick, let’s pack up the stall and go to Doctor Shen’s Medical Hall.”
He closed the stall and placed everything that had to be placed in the backyard of Shen’s Medical Center. Then, he went to the front to find Doctor Shen.
When Doctor Shen heard that they wanted saltpeter, he stroked his beard and smiled, “I still have half a kilogram of saltpeter in my clinic. If you want it, you can take it all.”
Xue Sifu didn’t even need to ask Xue Yan to know that half a kilogram would not be enough, but he couldn’t estimate the exact amount, so he looked at Xue Yan for help.
Xue Yan glanced at Jiang Yue.
To make ice from saltpeter, a large amount of saltpeter is required. A small or insufficient amount of saltpeter would not be able to freeze water at all. This was also why no one had discovered that saltpeter could make ice even after it had been known for so long.
Jiang Yue scratched her head and made a gesture of two.
Xue Yan understood and cupped his hands to Doctor Shen, “Half a kilogram would not be enough, we need about a hundred and twenty kilograms worth.”
Doctor Shen was so frightened that his beard was not even combed properly. He was silent for a long time before he asked, “Why do you need so much saltpeter for?”
He had been a doctor for so many years, but the total amount of saltpeter that his medical center had brought in was only two kilograms, that was all he had left.
Moreover, saltpeter was poisonous.
Seeing that there were no outsiders, Xue Yan trusted Doctor Shen, so he did not hide his true intentions, “To make ice.” He then told the older man about what he had read in a random book.
Doctor Shen stroked his beard again and smiled, “It could be possible to make ice. Alright then, I’ll try to get as much as I can for you.”
He has ordered more before. Usually, he would buy it according to the time when he bought the herbs. He had some connections in this area, so it shouldn’t be too difficult to get two kilograms worth of saltpeter.
“Doctor Shen, thank you so much for your trust.” Xue Sifu quickly expressed his thanks.
“What’s there to thank me for? We’re not strangers.” Doctor Shen laughed. “But, let me make this clear first. When you make ice, don’t forget about me and Yuxuan. Neither of us has ever eaten ice in summer. ”