Chapter 431 An unexpected breakthrough
The chief craftsman who made gunpowder for Xiao Xia was called Shao Fa. He failed in more than a dozen experiments, but gradually he figured out something.

“Your Highness, I have conducted repeated tests and found that the cause is still incomplete combustion. The combustion speed is too slow, and a large amount of gas is leaking out. In the final analysis, it is because the purity of the saltpeter is not enough.

I later tasted the saltpeter collected by the soldiers and found two things in it. One was salty and could burn, and the other was bitter and could not burn. The two things were mixed together and we couldn’t tell them apart. I guess this is why the saltpeter powder is impure.”

Xiao Xia nodded. The salty one should be saltpeter, and the bitter one is Glauber’s salt. One is potassium nitrate and the other is sodium sulfate. The two look so similar that the soldiers and craftsmen couldn’t tell them apart.

It seems that he can only wait for the saltpeter to arrive.

Shao Fa added: “I think that although the purity is not enough, if we can add substances with stronger combustion power, there may be hope of success.”

Xiao Xia nodded, “Keep experimenting! Tell me if you come up with a breakthrough.”

“I obey your orders!”

Shao Fa retreated, and Xiao Xia felt a headache. He originally thought that he could make gunpowder in one go, but now that he had encountered failure, his interest quickly faded. He let the craftsmen do it and he would not participate for the time being.

The next morning, Wang Anbang, the governor of Jian’an County, came to Jiangdu by boat. They came here on a sea ship. Xiao Xia was quite interested and went to Pier No. 1 on the Yangtze River in person to check the sea ship coming from Jian’an County.

There were more than a dozen seagoing ships, most of which were Fujian ships ranging from 5,000 to 10,000 dan in capacity. They were built with ironwood, joined with mortise and tenon joints and iron nails, and were extremely strong and sturdy.

“Your Highness, generally the ships built in Jian’an County are made of fir or pine, which have low corrosion resistance and can also travel by sea, but the risk is slightly greater. The ships built in Lingnan County are made of ironwood, which is very strong and sturdy, but the corrosion resistance is too high. One ship is equivalent to two of ours. However, considering the sturdiness, our official ships and navy warships are all built with ironwood, which can withstand the strong winds and waves in the deep sea. This time, I came here to give Your Highness a ironwood ship to build a 10,000-stone sea ship.”

Xiao Xia smiled happily and said, “Thank you for your kindness, envoy. Next year I will definitely take this ship to inspect Jian’an County.”

“I and all the officials warmly welcome Your Highness to come for inspection!”

Xiao Xia nodded, and asked with a smile: “Why did you bring more than a dozen large ships here?”

“Your Highness, we have to offer a large amount of tribute to the court every year. They are basically local specialties, such as tropical fruits, tea cakes, spices, and cotton. Last year, the fruits went bad on the way, so we didn’t bring any this year. So we have three categories: tea, spices, and cotton.”

Cotton is today’s wooden cotton. During the Sui and Tang dynasties, the imperial court would distribute cotton to officials as a welfare every winter, but it was distributed by the tael.

Xiao Xia smiled and said, “They are all tributes.”

Wang Anbang said embarrassedly, “Only one ship is tribute, the rest are what we brought here to sell. We are going to buy some pig iron, cloth, silk and porcelain when we go back. The silk and porcelain are for overseas trade, and the pig iron and cloth are for our own use.”

Xiao Xia smiled and said, “Are you planning to ship it to Luoyang and sell it, or just sell it in Jiangdu?”

Wang Anbang sighed and said, “This year, the coast has encountered a very strong storm. I have to rush back to provide disaster relief as soon as possible. I am not going to Luoyang, so I can only ask Your Highness for help.”

Xiao Xia happily said, “Then sell it to us! We also have the pig iron, cloth, porcelain and silk you need in our warehouse. Complete the exchange today and tomorrow, and you can go back the day after tomorrow.”

Wang Anbang was delighted and said, “Your Highness, please also send the tribute to the court.”

“No problem. I’ll arrange a boat to take you there.”

Xiao Xia then asked Jiang Xingyun, the director of the Warehouse Bureau, to negotiate the exchange with the other party.

The next morning, Jiang Xingyun, the director of the Warehouse Department, hurried to Xiao Xia’s office and bowed, “Your Highness!”

Jiang Xingyun was originally the magistrate of Chenliu County. Because he was honest and upright in his official duties, he was promoted by Xiao Xia to replace Sima Liu Huan. However, with the abolition of the Liangzhou General Administration Office, he also became unemployed. He received a meager salary and lived in poverty at home, waiting for the court to grant him an official position. This time, Xiao Xia also asked him to go to Jiangnan Road to serve as Sima of the Transport Commissioner’s Office, and concurrently served as the Director of the Warehouse Office.

Xiao Xia smiled and asked, “Have all the ships from Jian’an County returned?” “Your Highness, they have all returned. The price they offered was very cheap, and we gave them a lower price. Both parties are very satisfied.”

“Have they all been put into storage?”

“The others have all been put into storage. The cotton needs to be put into the grain warehouse. I will try to free it up today so it can be put into storage today.”

“Why does cotton have to be stored in the granary?” Xiao Xia asked puzzledly.

“Reporting to His Highness, cotton is too flammable and cannot be stored in ordinary warehouses. It must be placed in a granary with strict fire control. Two years ago, a cargo ship full of cotton caught fire and burned up in an instant. The speed was so fast that all 20 crew members were burned to death, and none of them had time to jump into the sea.”

Xiao Xia was stunned for a moment, as if he had thought of something, and a light flashed in his mind.

He thought of gunpowder cotton. Isn’t this a good combustion aid?

After thinking for a long time, Xiao Xia asked, “Have you ever seen cotton wool? Is it the peeled cotton wool or the cotton nut?”

“Maybe they have both! Because the prices are different, but the actual items are packed in big bags, and I didn’t take a close look.”

Xiao Xia stood up and said, “Let’s go to Pier 1. I want to see Mu Mian.”

He immediately took a carriage to the riverside dock.

What Xiao Xia wanted was cotton wool, which is the fine hairs at the bottom of the cotton seeds. After mixing it with sulfuric acid and nitric acid and drying it in the shade, he got nitrocellulose.

Although they did not have nitric acid and sulfuric acid at the time, they could dissolve saltpeter in water to obtain saturated potassium nitrate, which could be mixed with cotton wool and dried in the shade. Not only did it burn at an amazing speed, it also produced a large amount of expansion gas, making it an effective combustion aid to increase the power of gunpowder.

It can be used to replace part of the charcoal and added to gunpowder, making the gunpowder burn faster, the gas expand more violently, and the explosion effect better.

In the warehouse, the soldiers opened several large sacks filled with cotton peaches. Xiao Xia picked up a cotton peach and peeled it until only the cotton seeds were left, which were covered with fine wool.

This is it, try using it instead of charcoal.

Inside the big tent, Xiao Xia brought fire close to a ball of cotton wool. As soon as it was lit, there was a bang and the cotton wool burned up completely. The speed was so fast that Shao Fa, who was standing next to him, was stunned.

Xiao Xia smiled and said, “Got it? Let’s go back and try it out to see if it works.”

Shao Fa nodded and said, “I have taken craftsmen to various toilets to collect saltpeter in the past two days. I only want saltpeter, not bitter ones. I have collected dozens of kilograms. I will try a few more times and add cotton wool as well.”

Xiao Xia then warned: “Soak the cotton wool in concentrated nitrate water and dry it in the sun. It will burn even more fiercely.”

“I’ll remember this!”

Shao Fa left with a big bag of peaches.

At this moment, a female guard came running over and said nervously: “Second Madam, please go back quickly, the princess is about to give birth!”

“Ah!” Xiao Xia stood up suddenly and ran towards the back house.

(End of this chapter)