It's hard for my elder sister. I rely on the mountains to farm and pay off my debts.

Song Zhi put the pig pancreas in a wooden basin and temporarily placed it in her room.

In the afternoon, I went to Doctor Zheng's house and learned some more herbs from him.

She then asked, "Grandpa Zheng, I went to the grocery store today and saw someone buying bath beans. A small bath bean ball cost a hundred yuan. Why are bath beans so expensive?"

"I heard from the shopkeeper that these bath beans contain pig pancreas, which has excellent cleansing and moisturizing properties. Pig pancreas is not the most common thing, so how can it be sold at such a high price?"

Doctor Zheng stroked his beard and smiled, "That's because these bath beans contain medicinal herbs and spices, so they're naturally expensive."

"Medical books from previous dynasties record that bean powder was mixed with mashed pig pancreas and then added with cloves, patchouli, musk, agarwood and other spices to make bath beans."

"As the saying goes, an inch of fragrance is worth an inch of gold. Expensive spices like musk and agarwood are sometimes even more expensive than gold! Only royalty and nobles can afford them."

"In order to make this cleansing product available to more people, our ancestors reduced the use of spices and added affordable medicinal herbs to the bath beans."

"Since we're talking about this today, I'll introduce you to a few herbs."

"For example, Angelica dahurica, Atractylodes macrocephala, Rhizoma Aconiti Lateralis Preparata, Poria cocos, and Apricot kernel. Different herbs can give different effects to the bath beans."

"For example, Angelica dahurica and Atractylodes macrocephala can whiten the skin, while almonds are rich in oil and have a very good effect in moisturizing and maintaining the skin."

"Since you're interested, I've made some here. You can take some back with you when you go back!"

After saying that, without giving Song Zhi a chance to refuse, he immediately let Zheng Hui take some and give it to Song Zhi.

Zheng Hui turned around and took out a small wooden box and handed it to Song Zhi.

Song Zhi could only take it with a smile, and said, "This pig pancreas has such magical effects. I want to try making it when I get back."

When Dr. Zheng saw that she wanted to do it herself, he not only did not stop her, but was very encouraging.

He even took the initiative to tell Song Zhi about the specific method of making the bath beans, "If you have any questions after you go back, feel free to ask me."

After Song Zhi agreed, she thanked him very solemnly.

After identifying the herbs with Doctor Zheng, Song Zhi spent more than an hour learning Chinese characters with Zheng Hui, then happily returned home with the bath beans.

At this time, there were only a few children in the family spinning yarn in the yard, and all the adults went next door to help.

Song Zhi went to the next door and took a walk. Everyone had been busy digging the foundation and making adobe bricks these past two days.

Since she wasn't needed at the moment, Song Zhi simply went back home and started making pig pancreas soap.

Song Zhi brought a stone, then placed the pig pancreas on the stone and hit it continuously with a wooden stick.

Several children who were spinning under the eaves saw this and dropped their work and ran to Song Zhi, sticking their heads out to ask, "Sister, what are you doing?"

"You guys know about bath beans, right? My sister listened to Doctor Zheng talk about how to make them today, and she's trying to make some now."

"Sister is so awesome!"

The four children all looked at Song Zhi with starry eyes, their eyes full of admiration.

Song Zhi felt a little amused, so she told the children, "Go to the kitchen and get me some wood ash. It will be useful to my sister later."

The four little ones cried out and rushed to the kitchen one after another. Soon they rushed to Song Zhi with a basket of wood ash.

At that time, there was no snow-white alkali powder like today. The only way for people to obtain alkali was to mine alkaline soil rich in natural alkali on alkaline land during the dry season, and then process and refine it into alkali stone.

Since there is no alkali stone at home, Song Zhi plans to use wood ash instead and try to make some pig pancreas soap first.

Whether it looks good or smells good is not important for now, the most important thing is that it has a cleaning effect.

This also provides a reasonable explanation for her later improvements and upgrades in soap making.

Song Zhi was busy hammering and banging for a while, then added some mixed wood ash into the mixture and continued hammering.

When Mrs. Wu came back, she happened to see her granddaughter busy hammering and hammering.

She walked forward curiously and asked, "What are you doing?"

Song Zhi said calmly, "I'm making bath beans."

Wu became interested when she heard this. "Why do you put wood ash in bath beans? This black stuff is different from the bath beans I saw in the shop before!"

Song Zhi explained seriously, "Grandma, you must have heard that bath beans are very expensive, right?"

Wu nodded subconsciously. "Of course it's expensive. I saw other people buying it in the shop. I can't understand how such a small thing can be sold at such a high price!"

Song Zhi, "That's because these bath beans have medicinal herbs and spices added to them, neither of which is cheap, so it's expensive!"

"So after Doctor Zheng told me about the bath bean recipe today, I wanted to come back and try the simplified version. I thought, wouldn't wood ash be able to clean clothes? I might as well try combining the two. Who knows, the sum of the two might be greater than the sum of the two."

Mrs. Wu couldn't help but be amused by her granddaughter's words. She said cheerfully, "Okay, then you can try it first. If it's really as you said, then our family can afford bath beans!"

Song Zhi puffed out her chest proudly and said, "Grandma, just watch!"

Mrs. Wu shook her head and laughed, then went on with her own business without paying any attention to her.