This is a telescope

During a cross-country training, Marin was there to detect the terrain, but found that the distance seen by the human eye was limited, and it was impossible to see the distance. So Marin remembered the telescope. The telescope was invented at the beginning of the 17th century. There are still more than one hundred years from now. Marin had to find a way to create an "invention". Of course, as an advanced technology and a strategically advanced technology, Marin is not willing to let others know the existence of the telescope. So he went to the optical shop in the town of Robach, looking for the craftsmen in the store, and polished a number of circular concave lenses of the same size. Then he rode to another town, found the local optical shop, and let the glasses craftsmen in the store polish a batch of convex lenses (magnifying glasses) of similar specifications. Then he went to Vienna to find a craftsman who was good at making wooden crafts and built a batch of wooden barrels for him. The front and rear ends of the barrel are detachable spiral holders that hold the polished lenses.

Of course, in order to hide the lens, there is a length of wood barrel at the front of the deck, so that the glass inside can not be seen. If you don't pay attention, when Marin looks at the distance with a telescope, others think that Marin is observing something through a wooden tube.

However, what makes Marin depressed is that the quality of the glass in this era does not seem to work. The general glass is green. This is because the iron ions in the glass are not removed, so the transparency of the glass is not so good. The earlier optical glass, lead glass, appeared to be in the UK in the 17th century. Therefore, Marin can be sure that the telescope of this era will not look too far. Because the clarity of the glass is not enough.

Sure enough, a few days later, after Marin got the goods, he assembled the telescope himself, and he could pump a long length of wood barrel to adjust the focal length. However, no matter how Marin adjusts, the distance of the telescope is no more than 5 kilometers. Farther away, it began to blur. Even in a place of 5 kilometers, it can only be distinguished, and it cannot be seen clearly. Of course, this is used to detect enemy situations, which is much stronger than the naked eye. After assembling the two telescopes, Marin bought two wooden boxes and locked the telescope. The keys were only owned by him and could not be opened by others.

Later, in order to cultivate Schwartz (in fact, Marin decided to be lazy and let Schwartz do his daily work instead of himself), Marin organized several group confrontations. The confrontation was mainly carried out in the mountains, and Marin also took out the tactics of ambushing the mountains commonly used in the East. However, he did not dare to use the trick of smashing stones down the mountain, because this would kill people. Schwartz took the man with a hard time, carefully carried out a long journey, and then quietly touched the camp in Marin. What he didn't know was that at the height of the camp, Marin had already used a telescope, and he had clearly understood his deployment and marching direction 5 km away, and made corresponding adjustments.

When the 50 people of Schwartz touched the camp nearby, they directly faced the traps and encirclements under Malin order...

Others didn't understand it, but Kohler, who was not on the sidelines, seemed to understand something—it seems that Marin could make the corresponding subordinates, and it was related to the two cylinders he locked in the box. However, as a servant, it is not good to be inquiring. Then, Schwartz increasingly worshiped Marin.

After several exercises, Marin seemed to notice that Kohler noticed the cylinder in his hand. So, he felt that the cylinder in his hand seemed too conspicuous.

As a result, he once again found artisans, customized smaller lenses and smaller, less obscure cylinders, and assembled small telescopes again. This kind of telescope is very small, and Marin can cover most of the two hands, but it can also reach the observation distance of 5 kilometers. When Marin stood up high and looked at the telescope, others saw Marin's hands in front of him.

Thought that his hand is used to block the sun... In fact, his two hands hold a small cylinder...

In fact, the telescope is the most useful for scouts. Marin can watch the enemy line before the battle, but it is impossible to go out for investigation often (there are also general personally investigating, but the end is generally not good. For example, Li Zicheng personally went out to investigate and was armed to KO by an unknown landlord. Washington personally investigated It was almost slammed by Colonel Ferguson...). Therefore, he wanted to come and decide to develop the attendant Sauer into a scout. The reason why Sauer was chosen is because the Sauer family are their own serfs and are more reliable than outsiders. Moreover, Sauer's character is very calm and his mind is not bad. From the point of his recommendation of Schwartz, Sauer is also a bit wise. At least, he will look at people. Moreover, Sauer's vision is also good. In addition, when hunting, Sauer also often served as a investigative task, and there is some experience. He can come back to report the position without alarming the deer or wild boar, proving that he is suitable for investigation. Moreover, in this era, scouts often have to be close to reconnaissance, which is very dangerous. If you are not careful, you will be found and chased by enemy soldiers.

After you have a telescope, the scouts don't need to get close to the camp. Just a few kilometers away, find a high point and take out the telescope.

In an age when telescopes are not popular, even people with the best vision should be close to a kilometer to get some important data. Ordinary people should be close to a few hundred meters to see clearly. Therefore, people of this era, even if they do not investigate, will not exceed 1 km away. Therefore, as the first person to use telescopes to detect, in general, Sauer's safety can still be guaranteed. Later, Marin and Sauer exchanged in private. Marin tested the loyalty of Sauer and found it not bad. Then, he made Sauer swear that he would never allow anyone to disclose any news of the telescope. Moreover, every time Sauer went out to investigate, he could come to him to collect the telescope. Usually, the telescope used by Sauer is to be locked into Marin's box.

Not only that, Marin also asked that in front of others, Sauer should not use telescopes to avoid being seen by people. Sauer didn't care at first, but when he got the telescope, he was really shocked. The first time he used a telescope, he was almost scared from the telescope.

"This... this is amazing!" Sauer was shocked.

"Well, Sauer, remember, never disclose the secret of a telescope to anyone! Include your loved ones!"

"Yes, Master!"

"And, don't drink too much alcohol in the future. If you are drunk, it's easy to talk about it."

"Yes!"

"Okay, go!"

In the next few days, Marin arranged several investigation tasks for Sauer and taught him how to conceal himself and gave him a colorful investigation costume. After training, Sauer completed the task better than once. In fact, the difficulty of this kind of task is also very low. I will peek at the telescope a few kilometers away. Who will not do such a thing. The key point is to choose the right location to avoid being discovered by the other party. Moreover, investigation also requires patience. Fortunately, Sauer is a very patient person. If you are as tempered as Kahn, you will not have so much patience to count the number of each other, the number of animals and the details of the horses coming in and out. Of course, this involves knowledge of reasoning calculus, and Sauer certainly does not have that level. What Sauer can do now is to estimate the number of opponents through the house/tent, and to infer how many pots the other person has by the number of smoke raised during cooking, so as to simply infer the number of people eating...

These are the basic principles, and the Westerners in this era prefer to be hard-hitting. At this time, they will not think of any tricks to reduce the number of enemies. This kind of estimation is still relatively accurate.

In addition, Marin also stressed that Sauer should strengthen the observation and estimation of the enemy's food storage location. When the Europeans were in the Middle Ages, they would not think of ways to stabilize the hearts of the people by disguising the sand. Therefore, investigating the other's food reserves is also conducive to estimating the other's military heart (the grain is sufficient for the military to be stable), and even convenient for the party to destroy the other's grain.