Niter

  "All gunpowder is made from saltpeter, sulfur and charcoal. Saltpeter is of a yin nature, while sulfur is yang; when these two substances meet in a confined space, the resulting explosion is so great that it can shatter metal and stone." --- Song Yingxing, "Exploitation of the Works of Nature"

  Due to the problem of iron ore and fuel sources, Taiwan's pig iron production cannot be qualitatively improved. In this situation, Zheng Kezang, who actively requested to take over the Ministry of Works, did not put the first fire on the iron smelting workshop and official road expansion project after taking office as the regent, but unexpectedly intervened in the production of gunpowder by the Ministry of War.

  "The gunpowder production in our domain is carried out strictly according to the records of 'Wu Bei Zhi' and 'Bing Lu'."

  According to the official system of Ming Zheng, under each of the six officials equivalent to the deputy minister of each department, there was one more Langzhong in charge of specific departmental affairs. However, the Ministry of War was very special: on the one hand, the Ministry of War did not set up a military officer; on the other hand, Chen Xiangwu, who was equivalent to a military officer and was in charge of the Ministry of War's Zanhuazhang, was dismissed by Zhu Jin in a fit of anger. Therefore, Cai Qian, who had hoped to further his career as Langzhong, did not mind Zheng Kechang's usurpation of power at all, but instead hoped to make a good impression on the Regent Grandson by carefully explaining things to him.

  Among them, the saltpeter must be taken in three steps: first, put the saltpeter in clean water to dissolve and remove impurities such as mud and sand; second, add egg whites, red radish, etc. to the saltpeter solution and boil multiple times to absorb salt and sediment; third, use the newly condensed water glue to boil the saltpeter solution again, then let it cool and solidify in a ceramic pot, with waste water floating on top, mud sinking to the bottom, and pure saltpeter in the middle. Finally, remove the water and impurities, take out the pure saltpeter and dry it in the sun. The refined pure saltpeter is white crystalline salt, and only thirty kilograms of pure saltpeter can be obtained from one hundred kilograms of saltpeter.

  Zheng Kezang picked up a crystal of saltpeter presented by the military officer, played with it for a moment, and then gestured to Cai Qian to continue telling his story.

  The purity of sulfur has a great impact on the explosive power of gunpowder, and it is often said that more sulfur makes for horizontal fire, while less sulfur makes for vertical fire. To this end, our province has developed a four-step process for refining sulfur: first, crush the sulfur blocks and remove any sand or impurities; second, boil the crushed sulfur in water to remove impurities, then let it settle for a day before removing the sediment to obtain crude sulfur; third, mix 2.5 jin of beef tallow and 1 jin of sesame oil with every 10 jin of crude sulfur, then heat it until the oil no longer sticks to the sulfur, and add some birch leaves to the pot to boil together with the sulfur, removing any black residue that forms; finally, heat the crude sulfur in boiling oil until a yellow froth appears on the surface, then let it cool before removing the froth and impurities to obtain high-quality pure sulfur.

  Zheng Kezang listened to the explanation while secretly thinking in his heart. It's just that without pyrite, it wouldn't be necessary to extract sulfur in such a complicated and costly way. However, this is not something that can be said in front of Cai Qian, as it would only make the other person feel like he was talking nonsense and nitpicking, and might even give them a sense of frustration, like being slapped on the foot. It's also possible that Cai Qian would become dissatisfied because of this, so Zheng Kezang just listened quietly, without putting his thoughts on his face.

  "The quality of charcoal affects the speed and evenness of ignition, so traditionally only willow charcoal, cedar charcoal, and mulberry bark ash are used to make medicine. Among them, willow charcoal is the best, followed by the other two. However, even with willow charcoal, usually only willow branches before and after Qingming Festival can be selected, because at this time the leaves have not yet sprouted, and the essence is all in the branches, so the quality is the best.

  When selecting willow branches, they must be straight and even, and after removing the skin and nodes, they are naturally air-dried. Removing the skin reduces smoke, removing nodes avoids explosion during combustion, and also ensures that the fire burns evenly after ignition. Air-drying reduces moisture and improves the quality of the charcoal, which can then be carbonized and ground into a powder."

  When he heard this, Zheng Kezang said: "I have tried to make a dry kiln in the process of making cement, which also helps with the production of charcoal. The Ministry of War can send someone to understand how it is produced, or there may be some benefits. As for willow charcoal, the source is very strict. I suggest replacing it with bamboo charcoal, but it's just a suggestion. The Ministry of War may try to compare and make a final judgment."

  "Agreed!" Cai Qian, at his level, naturally knew what cement was and the role Zheng Kezang played in its production. He immediately agreed on the spot, and even made a decision in his heart that no matter how good or bad the dry kiln was, the Ministry of War would definitely build one. As for whether willow charcoal or bamboo charcoal was better to use, it was up to the subordinates to try and compare, so as not to "offend" the heart of this studious supervising grandson.

  Zheng Kezang was very satisfied with Cai Qian's understanding, so he smiled and nodded at Cai Qian. Cai Qian saw this and his face lit up even more, but he knew that Zheng Kezang's smile was a reward for his attitude, and whether he could really win the other party's favor still depended on his future actions. With this in mind, Cai Qian's enthusiasm ignited and he explained even more energetically.

  "With the above three materials ready, we can finally start making gunpowder. According to the "Binglu", the process is divided into four steps: First, grind saltpeter, sulfur, and charcoal into powder using a stone mill; Second, mix the three powders in a certain proportion with pure water to make a mud-like mixture, then repeatedly pound it 9,999 times until it becomes fine and even. If the mixture dries out during this process, add more water and continue pounding. After that, take it out to dry in the sun; Third, place the finished product on paper, ignite the gunpowder, and if the paper is not damaged after the gunpowder has burned out, it's a good product. Otherwise, it's an inferior product that doesn't meet the standards and needs to be pounded again until it reaches the highest quality; Finally, sift the gunpowder grains, break up the dried high-quality gunpowder blocks into grains of different sizes using coarse and fine sieves, and separate them for use in large cannons, flintlock guns, bird guns, etc. Those that don't form grains are used as ignition powder for fire doors, and all the remaining powder is discarded."

  "Hold on?" Zheng Kezang suddenly interrupted. "What Cai Daren just said, is the ammunition of our artillery really ordinary and nothing special?"

  In the memories left by Zheng Kezang in his previous life, there was a difference between the propellant of British firearms and artillery during the Opium War. Could this be one of the secrets why the Qing army's cannons had a short range during the Opium War?

  "No, no, it's I who spoke too quickly, the Regent has misunderstood." Cai Qian's explanation dispelled some of Zheng Kezang's doubts. "In fact, our imperial court has over fifty formulas for gunpowder, used in different types of firearms. This vassal state simplified them, and now the large cannons, such as the 'Dà pào' and 'Fó lǎng jī pào', use one formula, while the bird guns and 'Mì lǔ qiāng' use another."

  "I see." Zheng Kezang thought for a moment before continuing to ask, "How much of each of the two, saltpeter, sulfur and charcoal are in the medicine?"

  "What's this?" Cai Qian was taken aback, for this was absolutely confidential information. But Zheng Kezang's identity was different, so Cai Qian made a decision not to conceal anything in an instant. "The gunpowder is composed of saltpeter seven and a half parts, the remaining amount being sulfur and charcoal each accounting for half; the rifle powder is approximately composed of saltpeter seven parts six tenths, sulfur one part six percent, and the remaining amount is charcoal."

  Zheng Kezang compared the formula of the explosive used by the British army in the First Opium War with the two formulas used by Zheng's army, and found that they were quite different from the gunpowder and cannon powder formulas used by the British army more than 150 years later. It goes without saying that after more than 150 years of practice, the British formula should be more practical.

  "Lord Cai, I have two formulas here, you can try them out." Zheng Kezang reported the data. "The gunpowder contains 7.5% nitre, 1% sulfur, and the rest is wood charcoal; the cannon powder contains 7.8% nitre, 0.8% sulfur, and the rest is also wood charcoal."

  Cai Qian quickly recorded what Zheng Kezang said on paper with his flying brushstrokes. Before he could pick up the ink-stained paper to read it carefully, Zheng Kezang continued, "Also, whether it's cannon powder or gunpowder, the grains cannot be too large. It's best to make them all about the size of millet grains. The finer they are, the better, except for the powder. As for the benefits, the Ministry of War can compare with previous ones."

  Cai Qian was already frowning at this point, but Zheng Kezang wasn't finished yet. "It's best to package all the gunpowder in portions of 4 liang for cannon powder and 4 qian for gunpowder. Originally, it would be best to use silk cloth to wrap them, but our province is not wealthy, so using silk cloth would be too extravagant. Using paper that is slightly better quality would also work."

  Previously, adjusting the ratio of medicinal ingredients and the granules of the finished product may have some say, but at first, as long as the production quantity is not large, only after comparing and finding it successful will large-scale changes be made, the impact is not that great. However, using paper to set the dosage is different.

  To say nothing of other things, paper is not a cheap commodity in this era. Good paper is even more expensive and hard to come by. Zheng Kezang's mouthful would cost tens of thousands of taels of silver, and even Cai Qian, who was eager to please, hesitated.

  "May I ask, Your Majesty, what is the meaning of this?"

  "This is the shooting table made by the French gunners I invited." Zheng Kezang handed Cai Qian a piece of paper. "Of course, the shooting tables for each cannon are different, but if you just memorize the shooting table, you can know how much to raise or lower the barrel and how much to change the range after loading a few more or fewer packs of gunpowder." Zheng Kezang looked at Cai Qian's stunned expression and asked. "Lord Cai, don't you think that in the past, it was hard to find a good gunner like this?"

  "Is what the Regent said really true?" Cai Qian's breathing was disordered. He, of course, knew how difficult it was to train a skilled gunner who could hit the target ten times out of ten, and he also understood that controlling the range of the cannon could only rely on the gunner's intuition. But now, his past common sense had been overturned, no wonder he felt sincerely fearful. "Isn't that red barbarian just joking?"

  "He dares!" Zheng Kezang shouted in a domineering tone. "Lord Cai, rest assured that the Tongziying has been tested many times already. Except for the pitching on the sea and the need for further training of the gunners, the land-based cannons are already 80-90% accurate." To dispel Lord Cai's doubts, Zheng Kezang even extended an invitation. "If you still don't believe it, Lord Cai can come to the Tongziying artillery team to see for yourself."

  "Of course, I must go, of course, I must go." Cai Qian understood that he was witnessing a piece of history, so despite Zheng Kezang having set a precedent by taking out the iron mold to speed up casting cannons, he still wanted to rush over and confirm it as soon as possible. "Please arrange for the Regent!"

  "It won't work today, let's try tomorrow. All those related to the Ministry of War can go, but just take a look and keep it in your belly."

  "I understand." Cai Qian hastily assured. "I understand."

  "Since it's saved, I won't say anything more." Zheng Kezang was about to stand up when he suddenly sat back down. "Charcoal, our province can produce and dry on its own, but where will the sulfur and saltpeter come from?"

  "Sulfur is mostly imported from Japan and Ryukyu, and some are traded with the indigenous people in the high mountains of Taiwan. As for saltpeter." Cai Qian replied. "It can be extracted from nitrous soil, and the Ministry of War sends personnel to dig up saltpeter from pigsties and crop rotation fields every year."

  ??”

  "I'm afraid there aren't many." Zheng Kezang cut him off. "Go to Yinggui Li's merchant house and buy some, the people of Yinggui Li own several large mines in Tianzhu, they should be happy to exchange porcelain and tea for them."

  ??”