Salt is the top priority at the moment, and Fengyun is going to use the afternoon to plan in detail.

The more containers for water the better, the pottery is too late to burn, Fengyun picked up the bark of more than a dozen trees in the afternoon, ready to make a bark pot for backup.

The surrounding trees were all taken care of, and even the grass and vines on the ground were uprooted by him and braided into ropes for later use.

When he came to Neihu, Fengyun remembered that he had walked for nearly half a day, in order to save time, the next morning, before the sun rose, Fengyun got up early, made a simple back net with grass and rattan rope, tied the clay jar on his back, and drank it on the fresh water road with half a jar. The bark was rolled into rolls, tucked under the armpits, and the flint axe and flother were cared for, and Fengyun was ready to go.

The inner lake is still the liveliest place in the entire forest, and as the only freshwater source nearby, the forest creatures observe a strange balance around the lake.

Without time to take care of them, Fengyun crossed them with the clay jar on his back and walked towards the sea.

Perhaps because he was already familiar with the life in the forest, on the way back, Fengyun obviously felt that his leg strength was much stronger than before. It took me three or four hours to get here, but I walked less than two hours this time. And along the way, I was lucky, I didn't encounter any fierce predators, and walked back to the beach unharmed.

The old friend Pheasant Mother was very diligent in laying two eggs, but she was eaten ready-made by Fengyun again.

Haha laughed and dodged the attack of the pheasant mother, and ran to the beach in a hurry.

Returning to the place where he crossed again, Fengyun deliberately ran back to take a look, and after wandering around twice and found that there was nothing, he put down the clay jar and prepared to boil salt.

The history of boiling salt in seawater has a long history, the ancients called salt brine, but those who have studied junior high school chemistry know that acid and alkali salt are the three basic substances, and salt is not only edible salt.

The salt that people often say is actually sodium chloride, and there is not only sodium chloride in seawater, but also inedible salts such as potassium chloride and magnesium chloride. Although a small amount of salt is not fatal, it is always a harmful salt to the body, so you should not eat too much.

The coast where Fengyun is located has too many rocks, and there is no beach in sight, which is not suitable for cultivating salt pans, and he currently does not have the capital to make salt on a large scale, so it is important to get some salt and eat it himself.

Fengyun is very glad that he was not too indulgent in junior high school, and he listened to a few ears in class, plus he likes to play, and he didn't sneak away much when he did experiments in chemistry class, so he wouldn't be blind at this time.

He remembered that when he was doing the experiment, the teacher said that the salt content of the aqueous solution of sodium chloride was almost 20 percent, but the salt content in the seawater was only 23 percent, and the efficiency of boiling seawater directly to make salt was very low.

After filling a jar full of seawater and carrying it back to the shore, Fengyun found a leeward place, raised a fire, and put the clay jar on the fire to boil.

The firewood was uneven, and it was consumed quickly, and Fengyun had to run from the forest one by one, looking for firewood everywhere to burn.

The boiling efficiency is very slow, and the water surface can not go down to a punch in half an hour, and the sea water full of clay pots does not know how long it will take. But since he came, he couldn't run in vain, Fengyun had already decided, and he wouldn't go back without putting it on a bark pot of salt.

Keep adding firewood to boil, and it takes more than an hour for a tank of seawater to be boiled half-dry.

With the evaporation of water, a layer of gray crystals like limescale formed on the wall of the clay jar, Fengyun was very happy, this should be coarse salt.

After it cooled down, Fengyun scraped a layer of coarse salt with a thin piece of wood and put it in the palm of his hand.

"A method to obtain salt brine crystals and reward the extraction of sodium chloride*1. ”

Fengyun was a little surprised, he originally thought that after making a little coarse salt, he should be able to activate a skill, even if it was not chemical engineering, it should be some basic chemical application or something, but he didn't expect to give only a simple reward.

Looking at the method of extracting sodium chloride in his mind, Fengyun frowned, feeling that something was wrong. Anyone who can pinch a clay cup can activate a pottery skill, is it better to pinch a clay cup to make coarse salt?

From the reference of the salt production method in my mind, I know that these crystals in front of me are not directly edible, and the substances in these salt brine crystals are complex, and if you want to separate the inedible salts such as potassium chloride and magnesium chloride, you also need a crucial step - leaching brine.

The principle is very simple, and it actually uses the method of saturation solubility of different salts at different temperatures learned in junior high school.

Fengyun needs to boil a certain amount of salt brine crystals first, and then boil a part of saturated brine, spread the salt brine crystals on the support that will not leak crystals, but can seep water, and pour it with saturated brine.

The solubility of sodium chloride is affected by the temperature and the change is very weak, at the normal temperature of 20 degrees, the saturated solubility is almost 36 grams, and when heated to 90 degrees, it is only 39 grams, and the solubility of potassium chloride and magnesium chloride changes with temperature is more obvious. Taking magnesium chloride as an example, the saturated solubility is about 55 grams at room temperature of 20 degrees, but when heated to 90 degrees, it has risen to 70 grams.

Therefore, the saturated brine itself is an aqueous solution of sodium chloride that is close to saturation, so after pouring, most of the sodium chloride salt blocks on the support will not be dissolved, and the impurity salts such as magnesium chloride will be dissolved again. The salt cubes that have been poured are the salt that can be eaten directly.

Of course, there are still trace impurities in this, but it does not affect the consumption, if you want to eat more refined fine salt, just keep repeating this step.

The production method is simple, but Fengyun lacks a very important tool, and that is the right support.

In the method given by the system, the recorded support is made of bamboo mats, but where will Fengyun get bamboo from?

However, his carpentry skills gave him an idea quickly, so he found a few large trees that had been eaten by insects nearby, removed the outer bark, leaving only the inner thin bark, took out a complete piece as much as possible, stacked several pieces together, poked a bunch of holes with branches, flattened them, and fixed them on the branches tied into four squares, and a rudimentary filter device was ready.

The filter device took him an afternoon, and the seawater only boiled one jar, and all the salt brine crystals were scraped off to only one bottle cap, which was not enough at all, and it seemed that he had to stay at the beach for a few days.

There are no predators on the beach, only some seafood is busy, so naturally they can't escape the fate of being caught by the wind and clouds to beat their teeth.

Before dark, Fengyun picked up a pile of dry firewood and came back, and even knocked down a small tree that was eaten to death by insects and carried it back to the beach as firewood.

At night he was going to sleep here, while watching the fire, as long as the fire was not extinguished, he could avoid most of the dangers, not only to keep warm, but also to boil salt and brine, killing three birds with one stone.

After a busy day of running around, he was already very tired, but Fengyun did not sleep, lying by the fire and looking at the stars.

The Milky Way was bright, the stars were moving, and he remembered the heroic move that came out of nowhere. The world has been detached from his understanding, and after evading the pursuit of carnivores, there is a detached godly existence. Moving mountains and seas was as simple as breathing in their hands, and such a powerful heroic move was tightly a divine beast guarding the garden for the Heavenly Emperor, and it was hard to imagine how powerful the so-called Heavenly Emperor was.

The heavenly master in Gray Liu'er's mouth is a more inscrutable existence, and it can be seen from the conversation of Nine-tailed that she has received a number of thorough teaching etiquette, but the same cannibalism between Gray Liu'er's mouth and mouth closed makes Fengyun see some differences.

Knowing etiquette but not virtue, in the nine-tails, cannibalism does not seem to be an unacceptable thing, but he has only been taught a lesson by Yingzhao, and is forced by the so-called coercion of the gods who open human intelligence, so he has to eat, if it is a weekday, it can't think of it for a while, and it may not be able to eat it for himself? So, this is also the reason why he left the area of Qingqiu Mountain and ran back to Neihu.

However, what makes Fengyun a little unpredictable is the system hidden in him. Even if the divine beasts who are as strong as Yingzhao and the Nine-Tailed Fox are, in the eyes of the system, just a gene collection object, then what kind of height should the maker who designed this system stand on to classify these divine beasts into ABCD? This makes Fengyun can't help but think of a word, captivity.

The doorway in this is definitely more than what is in front of you, Fengyun sighed and muttered: "What's the use of thinking about this? I just want to return to the original world as soon as possible, don't drink blood here, the rest, what about love!"

The firewood was almost burned again, and Fengyun smashed the dry tree he had brought back with a flint axe for a long time before breaking a piece of the trunk and adding it to the fire. It was too slow, so he got up and walked around the beach, returning with a few rocks.

Throwing a rectangular stone chip wide at one end and one narrow at the end, Fengyun sat down, picked up the flint axe and knocked the end of the stone chip bit by bit, and he was ready to make another stone axe.

After acquiring stone skills, it is a bit unsightly to look at the shoddy flint axe. Although it is called a flint axe, the sharpness of one side is not called an axe blade, and in Fengyun's opinion, it should be called a flint hammer.

Carpentry also needs tools such as axes and chisels, and since they have to do it, they can simply do it together.

The reef, which has been washed by the sea for an unknown number of years, is definitely one of the hardest things on earth, and the wind and clouds can only leave a little white spot on the stone when they are struck little by little with a flint axe.

It's definitely a meticulous job, it doesn't happen overnight, it requires absolute patience. Fengyun is going to knock out a rough axe shape tonight.