Seeing that the fuse burned into the bomb, according to the speed of burning, it should have detonated, but the bomb did not move at all.

I waited a little longer, but it felt like a long time. Just when the four of them were in a hurry, they only heard a "bang", and the four couldn't help but lower their heads, and they could hear the sound of falling rocks and clods of soil not far in front of them.

The four of them looked up, only to see that a puff of black smoke was slowly dissipating, leaving a half-foot square crater on the ground where the bomb was planted. The stones at the bottom of the pit were also blown open, and large stones were scattered around the pit.

Guo Xingzu is nothing, he has already seen it last time he followed Zhou Nan. But Cai Xianzhong and Zhu Xian opened their mouths wide and couldn't speak for a long time.

Zhou Nan didn't care about admiring the surprised expressions of the two, turned his head to Guo Xingzu and said, "Guo waits for the edict, the speed and slowness of the lead are uneven after ignition, and this needs to be improved." Also, Zhu Zhizhao, you ask the soldiers at the gate of the village to catch a pig and a sheep from the north village, and get a wooden plank. Zhu Xian felt curious, and hurriedly ran over to find someone to catch pigs and sheep.

Cai Xianzhong said at this time: "Lord Dazhai, I have also seen earth-shaking thunder and fire cannons in the Southern Dynasty, but I don't have such power, I can blow up stones. ”

Zhou Nan said to Cai Xianzhong: "Can you and Guo Zhizhao write and calculate?" ”

Cai Xianzhong nodded and said, "Yes." It's just that I don't write much. ”

Zhou Nan nodded and said, "Wait for the two of you to record the effect of the test bombing, if there are any problems, how to improve, you have to write it down, so that you can improve it next time." Guo Xingzu and Cai Xianzhong both nodded.

Zhou Nan asked the two of them: "If this bomb is installed at the front of the arrow shaft, and then explodes after hitting the enemy, what is the difficulty in taking Yanjing?" ”

Cai Xianzhong suddenly realized: "It turns out that the owner of the big village plans to do so, but how to shoot and then blow up, but it's not something that the villain can come up with." ”

Guo Xingzu said with a sad face: "Dazhai master, the last time the wine altar bomb, the villain made a bamboo branch in it, connected it with a thread, and the wine jar fell to the ground and shattered, and the bamboo branch bounced off, driving the wire, and ignited the fire velvet fuse, and it exploded." ”

Zhou Nan said with a smile: "Guo Beizhao has set it up so cleverly, and this time he will definitely be able to make the ignition mechanism in the explosive arrow." ”

Seeing Guo Xingzu's frowns, Zhou Nan felt that Guo Xingzu was also a little embarrassed. To store the gunpowder in the bomb body, and can also take it out at any time and put it on the arrow to shoot it out and explode, which requires that the bomb usually has a safety device inside, and it will never explode when carrying, and it is also required that there can be ignition inside the bomb after it is shot, so as to ignite the gunpowder and explode. In the early days of hand grenades, only time-delay fuses were used, and friction was used to ignite the explosives inside.

Thinking of the friction and fire, Zhou Nan suddenly thought of the explosive arrow he wanted to make. The kinetic energy of the shot arrow can be converted into the kinetic energy needed when rubbing, thus using friction to start a fire. There are ready-made raw materials in the sulfur warehouse that rubbed the fire.

"Hahaha!" Zhou Nan communicated this layer and laughed, but Guo Xingzu and Cai Xianzhong were confused and looked at Zhou Nan strangely.

Zhou Nan said: "Wait a minute, I'll make you a little plaything." ”

As he was talking, he saw several soldiers leading pigs and sheep and carrying wooden planks.

Zhou Nan asked Guo Xingzu to install another bomb, and he picked a place where these soldiers tied pigs and sheep, and then erected the wooden plank next to it.

Guo Xingzu ran over with a bomb, and Zhou Nan asked Guo Xingzu to just put the bomb in a place where pigs and sheep couldn't step on it, and then let Guo Xingzu ignite the bomb. He and Guo Xingzu ran back to the hiding place to watch.

This time the fuse burned evenly and quickly, and with a loud bang, the bomb placed on the ground exploded. At the moment of detonation, the planks were blown out seven or eight feet away, and the pigs and sheep lay on the ground, and there was also a deep pit on the ground.

Zhou Nan led people over, only to see several wounds on the pigs and sheep, gurgling and bleeding, lying on the ground. The soldier lifted the plank back, and there were several holes in the half-inch-thick plank, and a piece of iron stuck to it.

Zhou Nan is basically satisfied with this result, but he doesn't know if he can break through the armor, and he will find a pair of armor to try next time. He asked the soldiers to carry the pigs and sheep down and send them to the canteen to stew, and today the meal was improved.

He asked Guo Xingzu to get him some realgar powder and saltpeter powder. In addition to sulfur, there are also realgar and other substances used in the preparation of gunpowder in the sulfur warehouse. Guo Xingzu brought some each, and Zhou Nan mixed the realgar and saltpeter with steamed wine, and then evenly smeared them on the two pebbles and put them in the sun. After Guo Xingzu read it, he didn't understand what Zhou Nan meant.

Zhou Nan said: "Wait for half a day and you will understand." ”

Cai Xianzhong and the four workers assigned to him collected iron blocks, chopped firewood, and prepared for the official smelting of bomb casings. Zhu Xian took three of his subordinates and began to burn the next furnace of charcoal.

Zhou Nan returned to Beizhai and asked Lao Zhengtou for paper and pen. Although the test explosion was successful, he was not satisfied, and the accurate ratio did not play a role in this era. Because the purity of the raw materials is inconsistent, the same ratio will have different effects after being made. Therefore, Guo Xingzu needs to adjust the ratio of gunpowder slightly on the basis of the original formula to see which ratio is the most suitable raw material at this time.

Science students can't do accurate calculations, so they can only use stupid methods, adjusting the formula every time to see which formula is the most powerful.

So Zhou Nan found some paper and pencils, and asked Guo Xingzu to take someone to make experimental records.

When Zhou Nan returned to Nanzhai, Guo Xingzu was already waiting for him next to two pebbles coated with realgar and saltpeter respectively. Zhou Nan first handed the pen and paper to Guo Xingzu, told Guo Xingzu to adjust the formula, and then took the pebbles, took Guo Xingzu to the dark, and knocked each other with two pebbles.

In the dim light, I saw sparks coming out of the impact as the pebbles collided with each other.

"Big village master, the villain understands!" Guo Xingzu said excitedly: "It turns out that these two things can make fire. If you fill it with some phosphorus powder, it is easier to ignite. The lord of the village is really a god, and the villain is going to try to make an explosive arrow. ”

When he was a child, Zhou Nan played with this kind of toy with his classmates: two round balls, coated with yellow powder, stuck to them, and the two balls hit each other, making a "pop" sound. When I was a child, of course, I didn't know that this was the composition of the bottom fire of the gunpowder gun, and the sparks emitted after hitting these two components ignited the gunpowder and shot a projectile.

At the moment, he can only make these rudimentary hot weapons, and when he has the territory and people, he really wants to try the feeling of building a musket army.

With the current level of science and technology, it is not impossible.

(End of chapter)