In the north of Xiyang City, in the lakeside manor of Xiyang Wangfu, in a courtyard, Xiyang Wang Yuwenwen, who had just been released, was looking at a large circle of cables on the ground, which was an experimental cable that had just been fished out of the lake, called a waterproof telegraph line. Pen × fun × Pavilion www. ｂｉｑｕｇｅ。 ｉｎｆｏ

Ten miles long, the iron wire is wrapped in eucommia glue as an insulating glue for the core, and the cost is six hundred times a mile, so this large circle of so-called waterproof telegraph wires cost Yuwenwen 10,000 runs.

What is this concept? According to today's rice prices, the money has always been able to buy two stone of good rice, so 10,000 yuan can buy 20,000 stone rice, which is enough for two months' rations for 5,000 people of the Hulin Army.

The telegraph line was immersed in water, and it was only 312 days to this day, and the telegraph line sunk at the bottom of the lake could not transmit the signal.

Without the insulation of eucommia ulmoides, the direct contact between the iron wire and the water will lead to leakage, so the two ends of the iron telegraph line naturally cannot transmit the telegraph signal, and if the waterproof performance of the telegraph line is not good, then it means that the telegraph 'water line' can not be practical.

Yu Wenwen, who was still talking and laughing with Yang Jigao at noon, is now like a frosted eggplant without energy.

He has always had ambitions, always fantasizing about one day putting the cable telegraph into practical use, and then conquering the world, but he is taught by the bloody reality that his technical level is too far behind.

Cable telegraph, as the name suggests, relies on telegraph lines to transmit telegraph signals, so if there is a physical telegraph line, then the question of laying telegraph lines must be considered: by land or by water?

By land, either with a telephone pole, then there is a possibility of being destroyed at any time, not to mention anything else, just the lack of iron and copper along the villagers or passers-by may be at any time.

Either buried in the ground, the trouble is not small: the line is very troublesome to maintain, and the person who cares will break the telegraph line buried in the ground, not to mention the problem of being soaked in water when buried in the earth.

Anyway, the telegraph line has to be waterproofed, so it is better to take the 'water line', that is, let the telegraph line sink in the river, which is not easy to be damaged by people, and there is no need to erect poles or dig trenches for wiring.

Of course, based on various considerations, a transfer station is needed at certain intervals, one is to facilitate troubleshooting, and the other is to facilitate the replacement of cables.

Especially in the Yangtze River basin, for example, from Xiyang in the middle reaches to Jiankang in the lower reaches, the waterway is about 13,400 miles, and if the telegraph line takes the 'water line', its safety is guaranteed: the water of the Yangtze River is so deep that thieves can't catch it even if they want to steal and destroy it.

It is relatively hidden, not as conspicuous as pulling the wire with a telephone pole, Yu Wenwen's wishful thinking is crackling: he secretly pulls a telegraph line from Xiyang to Jiankang, and he can control the Yangtze River basin area without knowing it.

In the future, Zhou Guoping and Chen unified the Central Plains, and he just relied on the telegraph line to transmit prices in various places, and relied on the ability of unpredictable prophets to transfer goods everywhere to buy low and sell high, and he would definitely become a new generation of 'Tao Zhu Gong'.

The premise of all this is to make durable waterproof telegraph wires, and rubber is not to think about, so Yuwenwen's first thought is lacquer and tung oil, and wrap the iron wire with tarpaulin 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 study of compressed gas technology, Yuwenwen already has a large area of Eucommia ulmoides Garden, so the amount of Eucommia ulmoides glue can still be guaranteed, and it is not easy to make a ten-mile-long waterproof telegraph line, he also thought that it could last at the bottom of the lake for two or three years, but it was finished in less than a year.

Ten thousand times have been lost, and then there is more depressing news.

The telegraph research team found that as the length of the telegraph line increased, the electrical signal at both ends of the telegraph line showed an increasingly pronounced delay, and after countless experiments, a possibility was estimated:

If the 1,3400-mile-long telegraph line between Xiyang and Jiankang is successfully laid, the telegram of 100 words sent from Xiyang to Jiankang will be received by Jiankang in about two or three hours.

Secondly, if you want to maintain such a telegraph line, the number of batteries required will be very staggering, and the cost will have to be calculated separately, if you want to estimate a total cost, the telegraph line (single line) from Xiyang to Jiankang will cost at least 900,000 yuan.

With this money, you can probably buy 9,000 fine war horses, and according to the configuration of one cavalryman with three horses, you can make up 3,000 elite cavalry with super mobility.

What is the concept of 3,000 elite cavalry?

In the early Tang Dynasty, Li Jing, the head of the marching army, led 3,000 elite cavalry of the Tang army to attack the Turks in Mayi, and defeated the Turkic Jieli Khan in Yinshan, killing more than 10,000 people and capturing more than 100,000 people.

Three thousand elite horsemen, that is a sharp sword, if used properly, is enough to turn the tide of battle.

Thinking of this, Yu Wenwen was in a trance: Nine hundred thousand yuan! I really have so much spare money that I don't use it to feed the cavalry, but to pull the telegraph line?

Well, the cable telegraph is indeed an artifact, but to come out with a practical waterproof telegraph line ... The widow can't do it!

Lin Youdi on the side saw Yuwen Wen stunned, and asked cautiously, "Lord Lang?" ”

"Huh? Well, summary, you have to summarize it well, write it into a report and hand it in. ”

"Yes!"

Ten thousand times were lost, Yuwen Wen was dripping blood in his heart, although he often burned money, but he had results, unlike this time, but he didn't blame his subordinates, because it was not the other party's responsibility.

Long-distance telegraph lines will have signal delays, Yuwenwen pondered that this is probably the resistance problem of telegraph lines, if you want to solve it, you have to add voltage, more than a thousand miles long telegraph lines need a lot of voltage.

It is very expensive to rely on batteries to stack voltage, so it is necessary to use hydroelectric power, but even if it can really make a practical hydroelectric generator, it is very likely that because the electrical foundation is not good, two people will be electrocuted in three days, and more than a dozen will die when they die.

Or switch to low-resistance copper wires, but how much copper does a telegraph line more than a thousand miles long?

The practical long-distance telegraph line needs the support of electricity and chemistry, and it is obvious that Yuwenwen at this time has no technical ability to support it.

The governor of Huangzhou, it is okay to raise 5,000 soldiers on the profits of trading, and it is simply delusional to build a thousand-mile-long telegraph line, unless the imperial court comes forward to preside over the construction, but Yuwenwen will not be stupid enough to hand over this kind of artifact.

The rope is to be put around the neck of others, not to let others put around their own neck.

Yu Wenwen turned around and walked out of the courtyard, looking at the sky, he fell into deep thought again: It can't go on like this, you have to change your thinking.

It's not early, and if you don't move back to the city, the city gate will be closed, but Yu Wenwen planned to spend the night in the manor tonight from the beginning, just to change his mind, I'm afraid it will be a sleepless night.

The cable telegraph is a bottomless pit, and there is no hope for practical application, and it has been stuck in the laboratory stage for two years, but Yu Wenwen is not reconciled, even if it takes another ten or twenty years, he will find out.

I'm still young, and my days are long!