After checking his identity and passing the gate, Zhou Jun walked into the West Academy of Taixue. As soon as he passed the main gate, he smelled a faint smell of fireworks.
Mao Shun on the side took a few careful sniffs and said, "This is the sulfur fire used by the alchemists, but the smell is a little different."
Going forward and passing through an inner hillock, he came to a courtyard with earthen ramparts built on three sides. Zhou Jun saw Jabir, dressed in gray robes, leading several food scholars and playing with something in the courtyard.
As he got closer, Zhou Jun looked up and down, and then he realized that Jabir's gray robe, which was originally white, had been smoked into dark gray by the fireworks.
The latter was squatting on the ground, repeatedly checking a broken wooden barrel in the pit that was constantly emitting black smoke.
Zhou Jun: "What's wrong?"
Jabir heard Zhou Jun's voice, stood up hurriedly, and said with some embarrassment: "The gunpowder did not burn fully, and the power did not achieve the expected effect."
When Mao Shun heard this, he was stunned.
It was unclear what was put in the barrel. After the explosion, a large crater two meters wide was left on the ground. Judging from Jabir's words, he actually said that it was not powerful enough.
Zhou Jun carefully approached the barrel and took a look. He saw that the gunpowder in the barrel had not been fully burned after deflagration, and most of it remained.
He ordered his subordinates to pour the gunpowder in the barrel on the ground. Zhou Jun took a closer look and saw the problem.
First, he dismissed the other people, leaving Jabir and Mao Shun alone. Zhou Jun pointed to the remaining gunpowder and said: "The gunpowder inside has been layered and agglomerated. This is the biggest reason for insufficient combustion.
."
"Layering? Clumping?" Jabir looked carefully and nodded: "Charcoal, fire saltpeter and sulfur, the three raw materials that were originally fully mixed, now separated again and condensed into blocks. What's going on?
?”
When Mao Shun heard this, he finally understood something: "You mean, charcoal, fire saltpetre and sulfur, these three things mixed together are the cause of the thunder just now."
Zhou Jun nodded and said: "This thing is called gunpowder. After being sealed, it will explode when exposed to fire. It can crack mountains and crack rocks. It is extremely powerful. It is the most secret weapon in the Anxi Army and must not be spread to outsiders."
Mao Shun stroked his beard and nodded solemnly.
Jabir held the gunpowder in his hands and was puzzled: "I obviously ground the three raw materials and mixed them thoroughly before loading them into the barrel. Why did this happen during the experiment?"
Zhou Jun: "Because of the specific gravity."
Jabir was stunned in place and looked at Zhou Jun: "Specific gravity?"
In his previous life, Zhou Jun had studied explosives-related knowledge at the police academy and was familiar with this area of knowledge, so he said: "Charcoal, fire saltpeter and sulfur, these three items have different proportions. After mixing,
During the transportation and charging process, re-stratification and agglomeration will occur due to bumps. Therefore, the combustion effect after charging will be greatly reduced."
Jabir had a headache and said, "What can be done to solve it?"
Zhou Jun: "The solution is simple, just change the gunpowder from powder to granular form."
Mao Shun listened carefully and asked hurriedly: "How to do it?"
Zhou Jun: "For each ingredient, use five kilograms of saltpeter, one kilogram of sulfur, and one kilogram of charcoal. The above total is seven kilograms, divided into three troughs, and it will be crushed for 5,500 times before it comes out. For each medicine, use three kilograms, and use one kilogram of good shochu.
, turn into mud, and then put it into the trough, then grind it a hundred times, and then come out of the trough. Mix it into grains, such as yellow rice or mung beans. It must be put into people's hands so that they don't feel hot."
Jabir opened his eyes wide: "Can making gunpowder into pellets really increase its power?"
Zhou Jun: "You will know once you try it."
Seeing Jabir getting up to try it, Zhou Jun grabbed him and said: "Today I will bring Master Mao to the west courtyard to meet you. In addition to gunpowder, there is another matter that requires the two of you to cooperate with each other."
Jabir: "What?"
Zhou Jun: "Now that gunpowder is available, the next step is to make weapons."
Mao Shun twisted the gunpowder powder on the ground with his hand and looked at the potholes on the ground. Suddenly an idea came to his mind and he asked Zhou Jun: "What Erlang said was to use gunpowder as a thrust and then use iron stones as projectiles to injure the enemy."
Purpose?"
Zhou Jun was a little surprised by Mao Shun's reaction speed.
The latter immediately nodded and said: "That's exactly it."
After finishing speaking, Zhou Jun used tree branches to draw a prototype of a primitive artillery on the ground, including the barrel, gun mount, muzzle, magazine, detonator, etc.
After drawing the structure of the cannon, Zhou Jun asked Mao Shun: "I have seen craftsman-made books. It is said that since the Eastern Zhou Dynasty, the folk have had the art of clay mold casting?"
Mao Shun: "Yes. Craftsmen use clay to make molds, and then pour bronze into them to form finished objects. This has been done since ancient times."
Having said this, Mao Shun paused for a moment and then suggested: "Bronze is expensive. If it is used to cast cannons, the cost will be extremely high. Why not use iron instead?"
Zhou Jun shook his head: "Let's use bronze as the material first, and the iron cannon will be slow for the time being."
Zhou Jun thought to himself that the biggest disadvantage of bronze cannons compared to iron cannons is that they are expensive, but they have many advantages.
for example:
First, bronze is stronger, can better withstand the shock during launch, and is more durable at sea.
Second, bronze is also easy to cast and can be remolded, and it is also easier to beautify and decorate.
Third, although the density of bronze is 20% greater than that of iron, bronze cannons are still lighter than iron cannons of the same size, so they can be used to create cannons with the same caliber and thinner tube walls.
Fourth, in addition to the above, the biggest advantage of bronze cannons over iron cannons is safety.
If a bronze cannon explodes, the barrel will at most be cracked, but if an iron cannon explodes, fragments will probably fly out, injuring the life of the craftsman.
In history, many famous cannon-smiths and soldiers who controlled artillery in the army were killed by the explosion of iron cannons.
Therefore, artillery began to be installed in the early 14th century. Until the 16th century, although bronze cannons were less numerous than iron cannons due to their high price, they were always the first choice for European armies.
Therefore, for safety reasons, Zhou Jun asked Mao Shun and Jabir to try casting the cannon in bronze regardless of the cost.
Jabir used charcoal and paper to copy down the structure of the artillery on the ground, and said to Zhou Jun: "Protector Zhou, there is one more thing."
Zhou Jun looked at Jaber.
Jabir: "The saltpeter used in gunpowder is consumed very quickly, and there is not much left in the warehouse in the West Campus. I sent students to the market to purchase, and there are very few materials in stock."
Zhou Jun smiled and said: "Don't worry about this. I have found an excellent saltpeter mine that can be mined in the open pit and has extremely rich reserves."
When Jabir heard this, he was shocked, and then worried: "If the mining area is far away from here, transportation and storage will be troublesome."
Zhou Jun: "It is located in Puchang, Xizhou (now Shanshan County, Turpan) under the jurisdiction of Beiting Protectorate, only three days' journey from Yanqi Town."
Mao Shun, who was familiar with the geography of the Tang Dynasty, was a little surprised when he heard this: "Is there a saltpeter mine in Puchang County?"
Zhou Jun smiled and nodded, and couldn't help but think in his heart, no wonder others don't know.
Shanshan County in Turpan City has the largest and only world-class saltpeter mine in China, and because it is an open-pit deposit, it is also very convenient to mine.
This saltpeter mine is located near Xiaocao Lake in the south of the county. Due to its remote location, it was not discovered until 2006.
Its saltpeter reserves reach an astonishing 170 million tons, which is comparable to the world's largest saltpeter mine in Chile. This knowledge point has even been included in the basic public security knowledge textbook of the police academy.
Therefore, the saltpeter mine owned by Anxi is an advantage that cannot be compared with other areas in Datang.
This was also the reason why Zhou Jun had previously asked Feng Changqing to serve as the governor of Beiting, holding two posts.