"Huh?" Steng was stunned by Su Fan's words.

"This circuit is a top-secret weapon that I have obtained with the Dreadful and Oak families, and I will be the one at present, if it is handed over to you, if those two big families are destroyed, I will not be able to cover you, even if Ricor and Alma are not in a rut. Su Fan said, in fact, she didn't scare Sten, she was afraid that the Oak family would not kill her because they didn't know if they had a backhand, and they also stuck some interests and would not sell them, but Steng was different.

The result, of course, was that Sten was frightened, he gave up learning this circuit, and left in a gray manner, Su Fan stood up with this made sonar, this sonar is just a core and shell, and the other parts are going to be done by Scarlet Moon, the listener is only a cylinder with a diameter of 30 centimeters and a length of about one meter, which looks like a small torpedo at first glance, which can be placed at the bottom of the battleship - in order to reduce the impact of the propeller, it is basically in the front, or directly as a tow.

The circuit part is finished, Su Fan wrote out the part that is needed for magic, the magic part is nothing more than energy supply and shock absorption and conduction, this thing is used in a similar way to the current commonly used listeners, but it is more accurate, and it can roughly judge the distance or something.

Such a big thing can't fit into the space bag, so she can only carry it back, and when she returns to the dormitory, it is already early in the morning - now Su Fan knows that Weishenme is half-dead every time he sees Sten, and he stays in the laboratory until the early hours of the morning every day, and it is already cheap for him not to be sleepy.

Carefully put this little torpedo under the bed, Su Fan took off his clothes and lay on the bed and then went to sleep, the next morning, her regular alarm woke her up, immediately jumped up from the bed, and called several roommates one by one to get up and get up, but several roommates refused.

"I don't have classes this morning...I don't have to wake up so early!" Rico waved his hand, reached out and rubbed Alma's chest a few times, then chose a comfortable position and put his legs on top of her and continued to sleep.

At this time, Su Fan remembered that the school's curriculum arrangement was very strange, the curriculum arrangement on the earth was a reincarnation of a week, but the curriculum of the Imperial Royal University of Glas was a reincarnation of a month, there were four weeks in a month, that is, there were 40 days in a month, and there was only one session of ballistics in the afternoon today.

Looking at the dark sky outside, the black sun was still going on, she extinguished her horse lamp, and then climbed into bed and continued to sleep for a while, only to be woken up by the scarlet moon in the morning, after the four of them washed their faces, they rushed to the cafeteria, and returned to the dormitory after eating.

Su Fan gave the list written yesterday to Scarlet Moon, Scarlet Moon looked at it and said that it was no problem, this Jishu can still do it, the materials or something Su Fan had bought yesterday, before the afternoon class, Scarlet Moon had already made things and assembled them together under Su Fan's guidance.

Because it's magic jishu involved, this microphone has only a torpedo-like body, and a knob to adjust the sound and a headphone - this headset and the knob to adjust the sound are prepared for the battleship, and the mechanic only needs this small torpedo, and the mechanic is fused with the mechanical spirit, and any function of the mechanical spirit can be transmitted to the brain instantly, and there is no need for headphones.

After a lesson, the four of them returned to their dormitories and circled around the little torpedo.

"Shall we try?" Scarlet Moon suggested.

Let's try it, after Scarlet Moon fused this listener with the mechanical spirit of his own speedboat, the four of them ran to the port, and ran to the sea in the small speedboat, where Scarlet Moon turned on the sonar and listened carefully to the sound from under the water.

"Well, I think I heard some kind of lapping water in that direction, a lot. Scarlet Moon frowned and said, it was the first time she used sonar, and it was very difficult to be able to identify the direction of the sound, and because she didn't know what that direction was and how big the real sound was, she couldn't judge what it was, even if she knew the conditions in front of her and wanted to judge the distance, only experienced sonar personnel could hear it.

"Hmm...that direction..."Su Fan got into Scarlet Moon's central control room, picked up a pair of headphones and put them on his ears, Scarlet Moon fused a complete set, so there was a headphone.

Su Fan listened to the sound in the water, and then compared it with the sound in his database, it should be a school of fish, and the sound of the fish is about the same size, according to this distance...Su Fan silently calculated, calculated the distance of the fish, the accuracy of this sonar seems to be good, even the sound of the fish can be heard, the jishu of the First World War actually used the effect of the Second World War, in which the magic guide jishu contributed a lot.

"Scarlet Moon, a thousand meters ahead, depth charges!" Su Fan put down his headphones.

"What?" Scarlet Moon was stunned for a moment, and at this time Su Fan remembered that this shijie had only just appeared in a submarine, let alone a depth charge.

"Forget it, I'll come..."Su Fan walked out of the central control room, stretched out his hands to the sky, and then a green magic array appeared behind her, and a spherical thing flew out of it, and after gliding in the air for about a kilometer, it landed exactly where the sonar heard a school of fish just now.

Boom~ This ball is a depth charge, the fuse is launched at a timed time of ten meters underwater, a thick column of water rises, and then the scarlet moon starts the boat and drives towards that position, after arriving at the explosion site, the four people on the boat searched on the sea with a searchlight, it may be that the power of the depth charge is too great, and after searching for a long time, I finally found half of the fish that had been fried.

"It's so big!" Scarlet Moon looked at the half of the big fish, if the fish was whole, it would be taller than herself!

"There really are fish!" Alma took out a stick and poked the half of the boiled fish.

This port is a place for students to experiment and train, even if there is such a big explosion, no one will come to see it, just save trouble, a few people continue to wander around this sea, this time it is not Su Fan who blew up, but Scarlet Moon and a few of them threw depth charges, the depth bomb in Su Fan's hand can also be thrown by hand, a few hundred kilograms, for three people is not an unacceptable weight.

After throwing a bunch of depth charges, several people finally received a big fish, this big fish was not blown up, but was stunned, and after being dragged to the boat, several people returned to the port, and quietly found a place, cut a few branches and started to grill fish, although Ricco and Alma are both eldest ladies of aristocratic families, but they have done wild adventures or something a few times, and they have also done grilled fish or something.

"Does this thing really produce energy?" Alma asked, eating the fish.

"Of course you can, but you need someone to learn something, but it's not hard. Su Fan spit out a fish bone and said, The use of an electric soldering iron can be learned by an ordinary person in a few days, let alone those alchemists who can handle a three-dimensional magic array with a complexity comparable to that of an integrated circuit.

The reason why Su Fan took out this sonar jishu is to make some money, although he has a lot of money, but it is still good to make money every day, and to pull up the scarlet moon is to reduce the risk, and the second is that those shops that are set out need her to take care of it personally, she doesn't have that ability, so the scarlet moon is a very haode coolie, and the third, of course, is to hug the thighs, the oak family and the fear family are two very large nobles in the Glass Empire, with these two families covering, some small troubles can be avoided.

After eating enough fish, the four of them put out the fire, and then returned to the dormitory, Ruike and Alma went to the communication room to send news to their family, this shijie's communication is a bit like the early days of World War II, some cities have magic nets, the magic network is to provide energy for some magic items, and the second is to provide a communication network - this communication network is not there when the city is out, and each city needs to use a communicator that conforms to the city's magic network, which is equivalent to a walkie-talkie for multiple people, but each walkie-talkie can communicate separately。

As for remote communication, it can't be done by one, remote communication is to use a small teleportation magic array to transmit the letter to the past, and on the other hand, according to the recipient's address on the letter, the letter will be sent over or notified to pick it up, a bit like the post office, but the delivery time has been canceled, although the teleportation magic array can also form a network, but not every city has it, and some cities have a new teleportation array, there is no time to network all the network, so that you can only use the relay method.

The Fear Family and the Oak Family are both big families, so the information of the special teleportation arrays of these two families can be found in the school's teleportation array, and the letters of the two were directly delivered to their respective homes, the Oak Tree is a little smaller than the Fear Family, the two families have been friends for generations, and the in-laws are continuous, and their respective interest chains are entangled together, if it weren't for the family tradition, Blood and some rights issues, the two families can be merged, Alma and Ricco have played since childhood, and one day the two rolled together when they reached estrus.

After sending the letter, the two returned to the dormitory, and the two families were stirred by these two letters, those elusive submarines did not bring much damage, but buzzing like a mosquito annoying, although many large pirates caused more damage than these submarines, but because of the strange attack of the submarines, the empire felt a headache, for which the emperor of the Glass Empire, Pytha Glass (strong I big Pythagorean. Lost his temper several times in the Senate.

The letter made everything clear, including the effect of sonar, the method of use, precautions, and the personal use of the two of them, and this kind of jishu that can accurately locate underwater objects made the two families ecstatic.