In a yard in the north of Xiyang City, in the manor on the banks of Wangfu Lake in Xiyang, Wang Yuwen Wen of Xiyang, who had just been placed in the yamen, was looking at a large circle of cables on the ground. This was an experimental cable just fished out of the lake, called the waterproof telegraph wire.

It is ten miles long, and the iron wire is wrapped with Eucommia ulmoides glue as insulating glue, and the cost is one mile and six hundred jin. Therefore, this large circle of so-called waterproof telegraph wires cost Yuwen Wen 10,000 jin.

What does this mean? At the current price of rice, you can buy two stones of rice for a coin of money, and then you can buy two thousand stones of rice for a coin of 10,000 coins, which is enough for the rations of 5,000 Hulin Army's 5,000 men. As a result, it is now wasted.

The telegram line was soaked in water. It was only 312 days until today. The telegram line sinking at the bottom of the lake could not transmit the signal. After a lot of effort, I took it up and saw that the outer layer of Eucommia rubber had rotted in many places, and the inner wire was obviously rusted.

Without Eucommia Glue Insulation, the direct contact between the iron wire and water leads to leakage, so the two ends of the iron telegraph wire naturally cannot transmit the telegraph signal. If the waterproof performance of the telegraph wire is not good, it means that the telegraph "water line" cannot be practical.

At noon, Yuwen Wen, who was having a lot of talk and laughing, was now like a frost-beating eggplant without energy.

He has always been ambitious and always fantasized about one day making cable telegraph practical and then spreading the world, but was taught by bloody reality: his technical level is too far behind.

As the name suggests, wired telegrams rely on telegram lines to transmit telegram signals. Therefore, there must be physical telegram lines, so the problem of laying telegram lines must be considered: 6 routes or water routes?

6-way, either use a telephone pole to pull the wire, then there is a possibility of being destroyed at any time. Not to mention anything else, villagers or passers-by along the route who are short of iron and copper may have bad intentions at any time.

Either it is buried underground, and the trouble is not small: the line is very troublesome to maintain, and those who are interested will break the telegram line buried underground, let alone the problem of being soaked in water when buried in the soil.

Anyway, the telegram wires need to be waterproofed, so it is better to go to the "water line", that is, let the telegram wires sink into rivers, which will not be easily damaged by people, and there is no need for vertical poles or digging trenches to wiring.

The ship only needs to carry a telegram line along the river. Of course, based on various considerations, a transit station is needed every certain distance. First, it is to facilitate troubleshooting and second, it is to facilitate cable replacement.

Especially in the Yangtze River Basin, such as from Xiyang in the middle to Jiankang in the lower reaches, the waterway is about 1,3400 miles. If the telegram line goes through the "water line", its safety is guaranteed: the water in the Yangtze River is so deep that even if the thief wants to steal the damage, he cannot catch it.

It is also relatively hidden, not as conspicuous as using a telephone pole to pull a wire. Yuwen Wen's wishful thinking sounded: he secretly pulled a telegram line from Xiyang to Jiankang, and he could control the Yangtze River Basin without knowing it.

In the future, Zhou Guoping and Chen unified the Central Plains. He could only rely on telegrams to convey prices in various places, and to transfer goods to buy low and sell high with the ability to predict the future. He would definitely become a new generation of "Tao Zhu Gong".

The premise of all this is to make a durable waterproof telegraph wire. Rubber doesn’t need to be thought about, so Yuwen Wen first thought of paint and tung oil, and a waterproof telegraph wire wrapped in a waterproof oil cloth to make a waterproof telegraph wire.

But the cost is too high and the effect is not satisfactory, so the further improvement is to use Eucommia Gum.

Because of the research on compressed gas technology, Yuwen Wen already has a large area of ​​Eucommia ulmoides garden, so the amount of Eucommia ulmoides can be guaranteed. He finally made a ten-mile-long waterproof telegram line. He thought he could last two or three years at the bottom of the lake, but in less than a year, he would be finished.

Not only did the 10,000 yuan beating, there was a more depressing news next.

The Telegram Research Team has found that as the length of the telegram line increases, the electrical signals at both ends of the telegram line have increasingly obvious delays. After countless tests, a possibility is estimated:

If the 1,3400-mile telegram line between Xiyang and Jiankang is successfully laid, and a 100-word telegram is sent from Xiyang to Jiankang, it will take about two or three hours before Jiankang will receive it.

Secondly, if you want to maintain such a telegram line, the number of batteries required will be amazing, and the cost must be calculated separately. If you want to estimate a total cost, the telegram line (single wire) from Xiyang to Jiankang will cost at least 900,000 jin.

This money can probably buy about 9,000 excellent war horses. According to the configuration of one cavalry with three horses, you can get three thousand elite cavalry with strong maneuvers.

What is the concept of three thousand elite cavalry?

In the early Tang Dynasty, Li Jing, the chief marching officer, led 3,000 elite cavalry of the Tang army to attack the Turks in Mayi and defeated the Turks in Yinshan, killing more than 10,000 people and capturing more than 10,000 people.

Three Thousand Essential Cavalry are a sharp sword. If used properly, it is enough to turn the situation around.

Thinking of this, Yuwen Wen was a little dazed: Nine hundred thousand coins! I really have so much spare money, so I didn’t use it to raise the cavalry but instead pulled the telegram line?

Well, wired telegraphs are indeed magical tools, but you need to create practical waterproof telegraph cables... I can't do it!

Lin Youdi, who was standing beside him, saw Yuwen Wen stunned and asked carefully: "Master Lang?"

"Hmm? Well, summarize it, you must summarize it carefully and write it into a report and submit it."

"yes!"

Ten thousand yuan was beaten, and Yuwen Wen was bleeding. Although he often burned money, he had achieved results at least. Unlike this time, he did not blame his subordinates because it was not the other party's responsibility.

Long-distance telegraph wires will have signal delays. Yu Wenwen thought that this is probably the resistance problem of the telegraph wire. To solve it, a voltage must be applied. Telegraph wires more than a thousand miles long require a large voltage.

It is very expensive to rely on batteries to build voltage, so you have to use hydroelectric power. But even if you can really make a practical water wheel motor, it is very likely that because of the lack of electrical foundation, people will be electrocuted every few days, and more than a dozen will die as soon as they die.

Or the telegram wire is replaced with low resistance copper wire, but how much copper does a telegram wire cost more than a thousand miles long?

The practical long-distance telegraph line requires the support of electricity and chemistry. It is obvious that Yu Wenwen did not have the technical ability to support it at this time.

The mere Huangzhou general manager is OK to support five thousand soldiers by relying on the profits of doing business. It is simply a delusion to build a telegram line that is thousands of miles long. Unless the court comes forward to preside over the construction, Yuwen Wen will not be stupid enough to hand over such a magical tool.

The rope should be put on someone else's neck, rather than letting someone else cover his own neck.

Yuwen Wen turned around and walked out of the yard. Looking at the sky, he fell into deep thought: If this continues, he will change his mind.

It was not too early, and if you didn't move back to the city, the city gate would be closed. However, Yuwen Wen planned to spend the night in the manor tonight, just to change his mind, and he was afraid it would be a sleepless night.

Wired telegraph is a bottomless pit, and there is no hope of practicality. It has been staying in the laboratory stage for two years, but Yuwen Wen is unwilling to give up. Even if it takes another ten or twenty years, he will still find out.
Chapter completed!