Open an aircraft carrier to fight against Japan

Lin Yuan hurriedly asked: "How can we let the school of fish come to us?"

Shen Wanqing said: "Isn't our sonar an active sonar? We can use the sound waves from the sonar to force fish schools to swim in our direction."

Lin Yuan asked: "What kind of sound waves can make fish swim towards us?"

Shen Wanqing said: "Animals can predict earthquakes and tsunamis, have you heard of it? Once we went to the Earthquake Research Institute to do counter-espionage work. We heard from the experts of the Institute that there will be low-frequency sound waves before earthquakes." , We humans can’t hear these waves, but animals can perceive them, so I think, if our sonar can simulate this sound wave, wouldn’t it be possible to drive the fish over?”

Lin Yuan said: "This method is really good. We can try it. Do you know what the frequency range of this sound wave is?"

Shen Wanqing said: "It seems that the frequency is relatively low, it may exceed the frequency range of our sonar emission, it seems to be below [-] Hz."

Lin Yuan couldn't help sighing after hearing this, and said, "Our towed sonar uses a minimum frequency of [-] Hz. If it is lower, the detection effect will be very poor."

At the moment of stalemate, Lin Yuan suddenly said: "I thought about it, our towed sonar is equipped with a communication module, and the frequency of the communication module can be lower than [-] Hz."

Shen Wanqing asked: "Why is there such a module on the sonar?"

Lin Yuan said: "This kind of module is used by us to communicate with nuclear submarines. The underwater communication of nuclear submarines is all done using low-frequency sound waves."

Lin Yuan gave the order, and the towed sonar immediately turned on the communication module, and experimented with the low-frequency sound waves. Finally, at 27 Hz, the fish began to appear restless, and their speed increased significantly. Three helicopters flew from three directions, like A large sheet wraps the school of fish in the core and drives the school of fish towards Lin Yuan.

The information carried by sonar sound waves is only the size, orientation and speed of the target. Different targets have different sound wave reflection shapes. If you want to know the enemy's ship and submarine model based on the sound wave information, you must conduct underwater acoustic reconnaissance on enemy warships and submarines in advance. , Record the shape of the echo, and build a database. In Lin Yuan's era, American reconnaissance ships repeatedly "strayed into" China's territorial waters. An important purpose was to record the shape of the echo of our warship.

So it's impossible for the operator to read from the echoes what kind of fish the school is made of, and if he can get down in the water and he knows biology very well, he'll find out that the school is Pacific herring, which is A typical pelagic fish that lives in seawater at a depth of five to ten meters.When the sonar emits low-frequency sound waves, the sound waves pass through layers of seawater and reach the bottom of the water, stirring up small yellow croakers and other species that live below 60 meters.

Both the fish in the upper layer and the lower layer were crowded together, rushing towards the position of Lin Yuan's fleet, the sea water became dark, and the experienced fishermen in the fleet began to exclaim, they had never seen so many fish.

Lin Yuan ordered the fleet to disperse and start to descend. The people on the water then started to get busy. They lowered the fish into the water and pulled them up again. They were full of fish, big and small. These fishing boats had ingenious designs. Underneath is a special compartment for fish. The outer wall of this compartment is latticed. Sea water can flow through the compartment freely, but the fish cannot swim out.

The location of the fleet, the sea water is relatively shallow. When the fish swim here, it is very difficult to swim again, so many fish are trapped in the fish, which brings convenience to fishing. Under the long-distance mobilization, more boats came from nearby to join the fishing army. Some boats really couldn’t hold them, so they went back to the shore first, unloaded the fish, and then came back to fish...

It wasn't until it was getting late that the fishing came to an end. On the way back, Shen Wanqing asked Lin Yuan: "You don't plan to send out helicopters to do this every day, do you?"

Lin Yuan replied: "I have already thought about it. Next time we will set up fences in the waters near here to regularly drive fish in, and then let the fishermen salvage it."

Shen Wanqing asked again: "But, with so many fish, can they be shipped out? If they are not shipped out, won't they rot?"

Lin Yuan smiled and said, "You will understand when you get to the shore."

When they got to the shore, they saw that the fish had piled up like a mountain on the shore. Many people were transporting the fish to the open space farther away. There were many women and children there, and they disemboweled the fish. , put salt on it, and let the salt prevent the fish from rotting.

After smearing enough salt on the fish, the fish was transported backwards to the state capital where the famine occurred. Lin Yuan had already informed Weng Tonghe of his follow-up plan before departure, so Weng Tonghe organized personnel to bring the needed food from all over the country. The salt was brought in, and a horse-drawn carriage was organized to transport the fish.

In the vehicle waiting area, Shen Wanqing also saw more than a dozen strange-looking big guys. In front of them was something like a boiler, and behind them were five carriages, which were very similar to trains, but they didn't walk on the rails. Shen Wan Qing pointed at them and asked Lin Yuan, "Is this a car?"

Lin Yuan replied: "This is considered a car, but it is powered by a steam engine, and its speed is slower than a tortoise. It can't outrun a horse-drawn cart. When they were built, they were originally intended to be transported on the battlefield, but They were too muddy to support the wall, and they had to be filled with water and coal after walking for a while, so they were abandoned, and now the transportation distance is relatively short and the load capacity is heavy, so we brought them here.”

Shen Wanqing nodded and asked, "When will the car be built?"

Lin Yuan thought for a while and said, "Don't worry, as long as the Northeast Governor is in hand, related industries can be established soon, such as petroleum, rubber, metallurgy..."

Before Lin Yuan could finish speaking, someone behind him shouted, "Lord Lin!"

When Lin Yuan turned his head, he saw a person approaching from a distance. After a closer look, he found that this person was Xu Bin from the Tianjin Machinery Bureau. There was a large bruise on the corner of his eye, as if he had been beaten. Lin Yuan Yuan hurriedly pointed to the bruise and asked, "What happened to your eyes?"

Xu Bin pointed to those cars and said, "It's not all because of them. There was no water in a steam engine on the road, so we stopped to add water. Who knew there was a weaving factory run by a British... "

Shen Wanqing asked from the side: "What is a weaving factory?"

Lin Yuan explained: "It is to weave textile raw materials such as silk and thread into finished products such as cloth or rope."

Seeing that Lin Yuan had finished explaining, Xu Bin went on to say: "When the British people saw our car, they bent over with laughter and said that the steam engines they eliminated recently were better than ours! We have a young Not popular, but I went up to fight, and I stopped in the middle, but the two of them didn't do much, and they punched me instead."

Lin Yuan and Shen Wanqing couldn't help but smile bitterly, Xu Bin asked: "I heard that Westerners have been able to make small machines that burn oil, put them on cars, and the cars run fast, my lord, you are very knowledgeable , I don’t know when we will be able to build a machine like that.”

What Xu Bin didn't expect was that Lin Yuan looked away blankly as if he didn't hear his words. Shen Wanqing poked Lin Yuan from the side, and Lin Yuan came back to his senses and smiled, "Mmm " Twice.

Xu Bin didn't pay attention either, so he left and Shen Wanqing asked, "What were you thinking just now?"