Throughout the history of mankind, whoever has mastered advanced science and technology has mastered the advantages of crushing. The reason why the Han and Tang dynasties are brilliant is because they stand at the pinnacle of science and technology, the four great inventions of ancient China have been in the leading position for a long time, and it is difficult for Western countries to match them.

So far, only two of the four major inventions have appeared; Compass and papermaking. From the perspective of modern people, the four major inventions are very simple, which absolutely does not insult the meaning of the predecessors, after all, each invention is the result of the countless explorations of the ancestors of the philosophers in the dark, and its appearance has extraordinary significance to the process of human civilization.

But for Liu Yin, who was born in modern times, these inventions are really simple, simple principles, very easy to find raw materials, and the scientific and technological process that changes history, for Liu Yin, sometimes it is just a gesture.

Among the four major inventions, only gunpowder is directly applied to the military, and gunpowder is the originator and cornerstone of all thermal weapons in later generations, and it has changed not only the course of human war history, but also the entire history of mankind, because of the emergence of gunpowder, and opened a new chapter.

There is no way to know when gunpowder first appeared, and it is clearly recorded in history that it was used in the Tang Dynasty, but the invention of gunpowder should be much earlier than this period.

Starting from the Laozhuang period of the Warring States Period, the emperors and nobles indulged in the fantasy of immortality, and drove some monks and Taoists to refine the elixir of immortality, and alchemy was rampant in the world, reaching its peak in the Han Dynasty. The so-called alchemy of intentionally planting flowers and flowers, unintentionally planting willows and willows, and pursuing immortality and turning iron into gold has failed without exception, but the gunpowder formula that was invented by chance has quietly changed the world, and it is not difficult to understand why this terrible murder weapon is very strangely named "fire".

**But it is extremely simple, sulfur, saltpeter and charcoal, the combination of these three things that do not match the boundary, but it is amazingly powerful.

Although Liu Yin is very familiar with firearms and even knows everything about them, he knows very well that without the technical support of modern industry, it is impossible for him to manufacture even a small screw, and under the existing scientific and technological foundation, if he wants to achieve rapid progress in science and technology, it is almost a fool's dream.

But this will never hinder Liu Yin's ambition, he is not a god, just an ordinary traverser who can no longer be ordinary, although it is impossible to comprehensively improve the scientific and technological level of this era, but in a certain aspect, a certain field to achieve cross-era transcendence, this is by no means a whimsical thing.

It is precisely because of the technological superiority over the Wei State that the Shu State, which is extremely lacking in manpower and material resources, has the capital to confront the powerful Wei State for more than 40 years.

Liu Yin has no research on cold weapons, not to mention that although the cold weapons of the Three Kingdoms era have not reached their peak, there is not much room for further improvement, and if he wants to make a qualitative breakthrough in weapons, Liu Yin has set his sights on gunpowder, one of the four major inventions.

Research and development of gunpowder, this is by no means Liu Yin's whim, at the beginning of the crossing, he already had a preliminary idea, after cracking the Qingcheng Mountain stabbing case, Liu Chan rewarded a large amount of gold silk, Liu Yin in addition to the distribution to the lieutenant's office colleagues, the rest of the part, has been handed over to the right Dao Feng Quan, by him to buy sulfur and saltpeter.

Fortunately, Sichuan was originally an important source of sulfur and saltpeter, as early as the Han Dynasty, Yizhou has the ability to mine sulfur and saltpeter on a large scale, and the quality of sulfur and saltpeter produced is also extremely high, which makes Liu Yin overjoyed, it seems that God really helps me, if you change to Jiangdong or the northern state and county, the raw material is enough for Liu Yin to have a headache.

Although Feng Quan was very curious, although Yizhou was rich in sulfur and saltpeter, the demand for these things was not too great, except for those Taoist priests who used them as alchemy, they really didn't find any other use.

In his subconscious, he thought that Liu Yin also used these to alchemy, in this era, alchemy is almost a habit of princes and nobles, in order to pursue the realm of immortality, many powerful people do not hesitate to spend huge sums of money to refine the elixir. Liu Yin was born in the Anping Palace, a powerful and wealthy family, if such a person came to alchemy, no one would suspect that he had other motives.

Feng Quan's ability to do things is very strong, although Liu Yin went to Hanzhong, but Feng Quan did not dare to discount the things he confessed, and a large number of sulfur and saltpeter were continuously transported to the Ma family manor, according to Liu Yin's requirements, these sulfur and saltpeter are of the best quality.

After Liu Yin took leave from He Zeng, he returned to Anping Palace, and he had not been reunited with his family for some time.

Liu Yin proposed that he was going to go to the Ma family manor to "alchemy", but Princess Ma was surprised. Although the status of Anping Wangfu is transcendent, Princess Ma has never believed in any immortality, and she sneers at the alchemy and gold techniques of the upper echelons of society, in her opinion, immortality is completely stateless, throughout the ages, even characters like Emperor Qin and Emperor Wu have never escaped the way of reincarnation, and the so-called alchemy is a complete waste of time and money.

There was a large amount of sulfur saltpeter in the Ma family manor, and Princess Ma naturally knew about it, but these things were all purchased by Liu Yin, and Princess Ma naturally did not interfere, at this time Liu Yin mentioned this matter, but Princess Ma couldn't help but nag a few words: "Yin'er, the techniques of Taoist monks are all false, if there is really an elixir of immortality in the world, what is the theory of future life, old age, sickness and death?" Have you seen how many emperors and magnates have been extremely poor all their lives, trying to find the elixir of immortality, but which one has succeeded? I don't feel sorry for the money, but I don't want to see you doing in vain. ”

Liu Yin smiled and said, "Who said that children are going to refine the elixir of immortality?" ”

"Then what's the use of you letting people buy so much sulfur saltpeter?" Princess Ma said with a puzzled expression.

"Alchemy is certain, but this elixir is not an elixir of immortality, as for what it is used for, it is not clear in a sentence or two now, on the day of Dancheng, you will naturally know." Liu Yin's smile is both mysterious and weird.