The strongest soldier

The tube is hollow and has the function of transmitting sound. The sound of stones falling into the water can be transmitted up through the tube. As long as you listen carefully, you can definitely tell through the sound whether it is the ground or the water below. Cao Xi has ancestral skills and can not only hear the sound of water , and you can also hear the approximate depth of the water.

Luo Zheng also understood the principle of pipe sound transmission and said in surprise: "Great, what should we do next?"

"The next step is easy." Cao Xi pulled the pole up and replaced it with a U-shaped metal head. The opening was extremely sharp, like a half-moon shovel. It could cut off a lot of soil with one shovel. Luo Zheng understood it at a glance. I was pleasantly surprised by the usefulness of this head. When I saw Cao Xi pushing the pole deep into the hole, he was about to ask a few questions. Cao Xi said with concentration: "Pull it from the bottom up so that the soil will not block the entrance of the hole. I will first Come on, you will take over in a moment, I think we can dig out a hole that we can go down in half an hour."

"Then it won't take more than two hours." Luo Zheng said in surprise. Seeing Cao Xi lowering the rod with a focused look on his face, as if he was feeling the depth, he did not disturb him and waited patiently while observing Cao Xi's movements to avoid turning around and taking over. The timing was wrong.

Cao Xi dug it down for a while, and each time he pulled it up, the distance was only one foot. He shoveled something down repeatedly. After a while, he pulled the pole up about one meter and continued to shovel it down. Repeatedly, gradually, his forehead Covered in sweat, Luo Zheng said regretfully: "How about I give it a try?"

"Not yet. You're not familiar with the technique. If you get into trouble, I'll shovel for a while and then switch to you." Cao Xi agreed casually and continued shoveling down to expand the hole.

Ten minutes later, Cao Xi enlarged the entrance of the cave to the size of his face. Cao Xi handed the pole to Luo Zheng and said, "Go down about twenty-five meters first, and look at the pole to estimate the distance, which is about this location." He pointed. A part on the pole, and then continued: "Pull it up about half a foot, and then try to shovel it down. Don't use too much force. It is appropriate to shovel the soil. Expand the bottom and then lift it up another foot. Repeat this That’s it, remember, you must make a round.”

"I understand, just keep an eye on the side and remind me immediately if something is wrong." Luo Zheng agreed, picked up the pole and stretched it down while carefully feeling the depth. After feeling the bottom, he lifted it up about half a foot. , tilt it slightly and shovel down, don't dare to use too much force, raise it slightly when you feel that the shovel can't move, then increase the intensity and continue shoveling down.

Cao Xi, who was next to him, saw that Luo Zheng was able to learn it immediately, and he was completely relieved. He said to Lan Xue, who ran up to watch the excitement, "We succeeded. It will be done soon. Is anyone else here?"

"We should be on the way now. I estimate we'll be there in an hour." Lan Xue agreed casually, looking curiously at the entrance of the cave. She felt like there was wind coming from inside. She couldn't help but be overjoyed and asked curiously: "The craftsmanship passed down from our ancestors." It’s really extraordinary. Is that your own specially made Luoyang shovel? I’ve heard its name for a long time, but I didn’t expect to see it with my own eyes. It’s indeed well-deserved.”

"I specially made it according to the Luoyang shovel. It is retractable and easy to carry." Cao Xi explained.

"As expected, it's so long. It shouldn't be light. You can actually carry it on your back? And I think it's easy for you to pull it up. How heavy is it?" Lan Xue asked curiously.

"About ten kilograms. It is made of special materials. If it is stretched more than ten meters, it will deform or even break if you use the wrong force." Cao Xi explained, looking at Luo Zheng who was continuing to shovel the soil, as if he didn't want to talk about this topic. .

Luo Zheng knew that this was Cao Xi's secret, so he didn't ask any more questions. He thought for a while and said, "If you are willing, I can come to you and apply. I can use special materials to help you build a new one. It should be able to solve the problem you just mentioned. We have the strongest research department in the country, of course, you have to be willing to do this."

"Really?" Cao Xi looked at Lan Xue in surprise. Seeing that Lan Xue didn't seem to be joking about him, he couldn't help but believe it and said gratefully: "This thing is not high-tech. You will know how it works after just one look. It’s done, the key lies in the materials, and I made this with great difficulty in buying materials. This kind of material is difficult for me to obtain, but it is not difficult for the country, so thank you very much.”

"It's no problem if you can get it. If the rescue is successful, you should be the first to make a contribution and should be rewarded." Lan Xue said with a smile.

"We'll talk about the details of aviation materials after we get back." Cao Xi said, continuing to stare at the pole in Luo Zheng's hand. Seeing that Luo Zheng's movements were becoming more and more proficient and standardized, he couldn't help but be overjoyed and said with a smile: "Your leaders are pretty good at it." Tong, I have a good grasp of the technology.”

"He is not my leader, he is my man. We are on the same level, but he has the final say about the war, and I have to listen to him." Lan Xue smiled, looking at Luo Zheng with a more obsessed look.

"Ah?" Cao Xi heard this for the first time. He was pleasantly surprised and said with a smile: "No wonder you two have a close relationship along the way. It turns out that's the case. Congratulations, you have found a good man."

"You're not bad either. Shi Qian keeps his word, values ​​love and justice, and is also a good man." Lan Xue said with a smile.

"Yes, there are not many such good men left." Cao Xi said, with a happy smile on his face.

Half an hour later, Luo Zheng doubled the size of the hole, which was enough for one person to go in, but it was not enough. He couldn't go down with his military bag on his back. He put the pole aside to rest, looked at Cao Xi and said, "You This tool is good, and this method of digging holes in the ground is also wonderful, saving time and effort."

"The premise is to accurately determine the location of the underground river." Lan Xue smiled beside him.

"That's true, but Cao Xi's judgment is very accurate. He only needs to expand one more round before he can go down. He can go down as soon as the large force arrives." Luo Zheng said to Lan Xue happily, then looked at Cao Xi and continued to add: "You made the first contribution in this battle, and it is also the first achievement. I thank you on behalf of the brothers."

"Let's wait until we rescue people. The seabuckthorn trees here are dense and the entrance to the cave is not easy to find. As long as you sprinkle the sand and soil around it, no one will notice anything abnormal after the sun shines tomorrow. But there is no guarantee that someone will search here and arrive." How can we evacuate at the right time?" Cao Xi reminded worriedly.

"Do you think it's okay to walk along the underground river as far as you can, then dig a hole and climb out?" Luo Zheng asked thoughtfully.

"It's not impossible, but we don't have much food, so we don't know if we can carry it." Cao Xi reminded.

"I will solve this problem. You have solved the problem of going down. Then you can find a safe place to dig a tunnel for us to come out. You don't have to worry about anything else. Of course, according to the agreement, you can also evacuate now. I will provide you with Enough food and water, provided you don't betray us if you are arrested." Luo Zheng said seriously, looking at Cao Xi calmly.