In the early morning, when the sun shines across the ridge and into the ravine, the earth boils again. [This chapter is first published, Love, Have, Voice, Novel Network, please remember the URL]

The sound of cannons!

The rumbling sound of cannons echoed in the mountains, the sharp roar of field cannons and the dull cry of mortar cannons echoed between heaven and earth.

The roar of cannons made the valley boil again, and among the white gunpowder smoke, the red dots and lines began to head towards the fortress on the top of the mountain.

When the troops began to attack, Yu Shujie, as the commander of the Front Wing Army, was filled with anger. His expression seemed even more anxious.

Four hours ago, before the sky was dawn, Yu Shujie woke up on the camp bed. When he opened his eyes, his first feeling was anger, not helplessness. Now, when he looked at the small fortress on the top of the mountain through the morning light, his anger became even more intense and his breathing became even more rapid.

"Um……"

Like the officers and soldiers of the Ming army, Yu Shujie wore a straight military uniform. Of course, because of summer, he was not wearing a woolen military uniform, but a wear-resistant canvas military uniform, with a field telescope hanging on his chest - this kind of telescope that cannot be retracted was welcomed by the army because of its sturdy and collision resistance. His left hand was placed on the handle of the saber.

This saber was given by His Majesty the Emperor when Yu Shujie was promoted to a general in the third year of Xingqian. Although this saber was not gorgeous, it was also made by a famous craftsman. He just held the saber and stood on a protruding slope in the valley, staring at the foreword with his eyes tightly.

The sun slowly crossed the ridge, and a ray of sunlight shone on his thick body. Under the bathing of the sun, he felt a little stuffy, and some sweat came out of his left hand holding the saber.

"It's been half a month..."

As he muttered this sentence in his mouth, Yu Shujie's breathing became a little rapid and his eyes became more and more serious.

Lieutenant Colonel Tian Liyuan stood half a foot away to his left, and his eyes were also looking at the fortress. Ding Guoming was his orderly soldier, holding a tall black horse behind him. If there were any reporters here now, they could observe him from a distance, and then draw his side image with a pencil, and publish it in Ming Pao, Daming News, Tianchao Weekly or other important newspapers and magazines, and then add the column title "Liupan Mountain pointed by General Yu's sword". Of course, such a news may be used to praise him, but in fact, Yu Shujie was extremely dissatisfied with himself!

Yu Shujie, the commander of the Front Wing Army, knew that although the Front Wing Army he commanded had only more than 20,000 people, there were only 6 battalions of infantry, 2nd Battalion cavalry and 2nd Battalion artillery. This was just a vanguard force in the army of this Western Expedition. The situation on the battlefield is now very obvious. The Ming Dynasty had put the noose around the neck of the Qing Dynasty and was waiting for the final stifle.

However, the fortress along the way made the final stifle difficult.

Half a month!

After delaying half a month in front of a fortress, how many fortresses will be left next? Will the war be extended indefinitely? Do you want to chew on one after another like ants gnawing on bones like now?

"Today should be over..."

Thinking of receiving the report before, Yu Shujie felt much better and his breathing became smoother.

"General."

Tian Liyuan turned his face and said to Shujie.

"Once the Engineer Brigade completes the blasting of the fortress, the 35th Battalion will start attacking."

Yu Shujie nodded.

He chose the 35th Battalion, the most elite of the Front Wing Army, to take on this decisive attack. Sun Yicheng, the battalion commander of the 35th Battalion, was not tall, but extremely capable. He was a veteran of Long in Jiangyin. He knew this fellow countryman. He believed that Sun Yicheng could complete this task. Moreover, many soldiers of the 35th Battalion had been baptized by all the battles of all sizes and battles since Tongguan, and they were reliable.

As long as the blasting operation of the engineers is completed, the 35th Battalion will definitely be able to knock down the fortress.

"If it weren't for the mountain..."

Thinking of the past half month, the engineers dug an explosive tunnel in the hard mountains, Yu Shujie felt anger coming again.

It is the special terrain of the mountains that delayed the attack speed.

"In another hour, you can perform a blast!"

When Yu Shujie urged the engineers to speed up, an oil lamp illuminated the fortification in a simple civil fortification less than 100 minutes from the top of the mountain. In the fortification, the sound of metal hitting came from a cave with a height of only two feet wide. In the past half month, hundreds of engineers have been digging a tunnel of hundreds of minutes in the belly of the mountain day and night with hammers and steel drills.

When they were digging tunnels in the mountains, the attacking troops were actually feint attack troops. Although they seemed to have fierce attacks, they actually kept using small and medium-sized forces such as squadrons and brigades to prevent the Qing army from discovering and doubting the construction attempt of the Ming army. Even at night, they would bomb them at any time and bombard them from time to time. The Qing army was exhausted, dizzy, and miserable. Under the cover of artillery, bombing, and feint attacks, the Qing army's attention was distracted, but the progress of the project was not fast. After all, they needed to dig a tunnel in the mountains.

Compared with the past, after ten years of technological improvement, the Ming army's engineers have now mastered extremely advanced tunnel excavation technology. Accurate measurements have prevented the tunnels they dug from deviating, and the blasting charge is extremely scientific. It will not waste too much gunpowder, nor will it lead to insufficient power and inability to destroy city walls or fortresses.

Although the construction difficulty increased greatly when entering the tunnel, the first was that the working surface was narrow, and the second was that it could not be operated upright, which greatly reduced the progress. However, after half a month of continuous construction, the tunnel finally dug to the bottom of the Qing army fortress. After measuring the location and determining that the Qing army fortress was above the tunnel, with a command, the soldiers immediately began to carry boxes of gunpowder into the tunnel, and soon as 5 tons of gunpowder were loaded into the tunnel medicine room.

The medicine room is located directly below the main fort, and the tunnel is 90 degrees and the excavation is very rough. In fact, it is enough to load explosives. After the explosives are loaded in place, some special fixing and protective measures are taken for the detonator and the firing line, the engineers began to exit the tunnel, and then turned back and filled a lot of soil, built with multi-layer burlap bags, and tightened it together with the steering part of the tunnel and most of the tunnel are tightly sealed.

"The angle determines the deviation, the level determines the height... It is an extremely simple thing outside the tunnel. After entering the tunnel, it is not the case. It is not easy for construction personnel to master..."

While the engineers were making final preparations for blasting, Sun Yicheng, who was waiting for attack at the second strike point, listened to the captain of the engineering brigade explaining some problems with the tunnel blasting operation.

In order to illustrate these things, Li Yinan, the captain of the Engineering Brigade, squatted on the ground, drew several lines on the ground with branches, and gestured two figures to Sun Yicheng on his palm.

One is a right-angle triangle. After drawing this figure, he explained.

"No matter how the altitude of the main peak is, as long as the ground centers of the two tunnel entrances are "zero height", "zero angle", and "zero distance" are measured or calculated using various instruments or after calculation, the relative height of the main peak, the straight line distance and orientation of the medicine chamber height and the tunnel entrance..."

Sun Yicheng didn't know much about these professional terms, but it did not prevent him from understanding the key from graphic perspective. Now he is like a student, where he is seriously studying this kind of explosion homework.

"What is this?"

He asked, pointing at another image.

"This is a blasting medicine room."

Holding the branch and pointing at the medicine room on the ground, Li Yinan explained.

"...A straight line reaches the head, then turn ninety degrees, like the shape of a "t". The purpose of this is that if the medicine room is located in the middle of the tunnel, it must turn ninety degrees, otherwise the power of the explosion will be greatly lost along the tunnel. No matter how sealing it is, it is like paper, and it is useless at all. If it turns ninety degrees, it is equivalent to distributing 50% of the longitudinal blasting force to the horizontal direction, and the steering and tunnel are completely closed. At the moment of explosion, huge energy is generated, just like a gun bullet that is out of the bore will not turn. The power of the explosion can be exerted to the extreme and the main castle above will be completely destroyed..."

Li Yinan looked a little proud when explaining, and he even said specifically.

"This blasting operation method was studied with several teachers when I was studying engineers in the Army School."

His words made Sun Yicheng look at him in surprise.

"You invented it? How about it, can you solve this sacking in one go?"

Facing the battalion commander's inquiry, Li Yinan said confidently.

"Please rest assured that the person in charge of each tunnel is the person I personally selected, and all the engineers have been strictly trained. Each squad leader in the squad must move forward for five searches without deviation, digging the steps, and use this distance as the basis. At that time, the steps of the Yishui platform are built, such as the platform of the stairwell. Each step is up and forward five meters, and so on. Each platoon leader must ensure that he has made ten searches without mistakes. Use the dug tunnel as a reference, and after I check and confirm, continue to advance forward and upward. Now the medicine room is located directly below the fortress, with 5 tons of gunpowder, not much more, and less less. According to the formulas such as soil quality, depth, explosion range, explosive equivalent, etc., I repeatedly calculated that a total of 2.5 tons of gunpowder was needed to blow up the fortress of the Qing army."

Looking at Sun Yicheng, Li Yinan added.

"It doubled the specified standard enough to level the entire fort."

"If this is the case, wouldn't it mean that the fortress can be blown up in an instant, and then brothers will not need to attack at all?"

"Um……"

Li Yinan replied casually.

"It's almost the same, but there will inevitably be some fish that miss the net."

While the two were talking, the sound of guns echoed on the battlefield from time to time, and the feinted troops were still covering the work of the engineers. After all, the feinted attack will not stop until the engineers complete their final preparations.

It was not until the engineers had completely exploded the tunnel and began to evacuate the tunnel that the feint attack troops stopped attacking and evacuated backward from the blasting range. At nearly noon, they had all retreated to a safe position.

"call……"

Hiding in the trenches, Li Yilang stared at the Qing army's fortress. Like his comrades, he looked at the Qing army's fortress with eager eyes. They had learned from the commander that their previous task was to cover the work of the engineers. Now the engineers have completed the preparation for the blasting operation. As long as the fuse is pulled, it will take no time for this seemingly insurmountable fortress to be razed to the ground.

"They retreated!"

Li Buting, hiding behind the perforation, looked at Ming Jun who was retreating, and looked at the red figures retreating. For some reason, a wave of ominous signs surged in his heart.

"Something is definitely wrong!"

Although I didn't know what was going on, Li Buting still felt uneasy in his heart.

"Today, the dog retreated can be very nimble."

"Not!"

"When did they retreat so simply?"

"Don't be careless!"

When the Qing army in the fortress stared at the retreating Ming army in confusion, he was speculating on the unusual actions of the Ming army in confusion.

Yu Shujie stared at the stone five-star bastion, his lips raised slightly, and he ordered coldly: "Detonate!"

As soon as his order was delivered, a messenger fired a signal flare in the air with a signal tube. Seeing the fire dragon dragging out of the air, Sun Yicheng issued an order ahead. The engineers near the tunnel immediately pulled the fuse and ignited the fuse, which burned in the bamboo tube towards the end of the tunnel.

Because the fuse is more than ten meters long, the waiting is anxious. When the ignition engineer fled into the trenches, Sun Yicheng stared at the fort anxiously, waiting for the moment when the fortress was razed to the ground.

One minute.

Two minutes.

Three minutes...

After waiting for more than twenty minutes, with a shocking sound, the seemingly solid mountain collapsed like a paper-blocking. The mountain and the fortress on the mountain were shaken, and the entire mountain was blown upwards.

The mountain top was overturned and leveled. The basin was completely informed. There were only a dozen people in the Qing army in the basin. Even if they were not dead, they would be stunned by the bombing and were shocked. In the smoke of the explosion, a cannon barrel flew half a mile away with the bombed rock, landing at the foot of the mountain and even killing a horse - this was the only casualty in the last battle against the Liupanshan Fortress.

After the local shaking mountains, as the smoke slowly dissipated, the soldiers in the trench stood up in shock, staring at the flattened hill and murmured on their lips.
Chapter completed!