Chapter 157: Fighting wits but not strength

Su You picked up the lotus root slices on the plate: "Now that the weather is hot, the nutrients are taken to grow leaves and bloom, and the lotus root is not very delicious without powder." Besides, isn't this Meishan lotus root you want to take back and plant? Don't you get tired of eating every day? ”

Ah Homi turned over the chopsticks and muttered, "I want you to take care of it!" How much can I eat for hundreds of pounds? ”

Su You persuaded with good words: "I mean, since it's not delicious, why waste it?" Wouldn't it be better to get some seasonal vegetables? ”

Ah Mi shouted: "Who said it is not delicious! It's so delicious, you dare to say it's not delicious?! Less nonsense to have a drink with me! ”

Uh, there is no common language left, Su You categorically refused: "I'm a puppy when I drink with you again!" I'll just drink tea! ”

The two siblings quarreled and put down chopsticks, and after a while, the hunting team returned.

Chaogu and Shitong carried a wooden stick, and in the middle of the stick was a muntjac with hoofed holders.

There were two pheasants hanging from his waist, and Li tied a string of turtledoves on his shoulders.

Chen Daxia didn't have any prey, he was dangling a flower crossbow in his hand, and when he saw Su You, he shouted: "Oh, let's eat first behind our backs!" ”

Su You smiled: "Yo, I have gained a lot." ”

Chen Yu said: "That's right, Brother Chao is super fierce, and the muntjac was shot by him with a big bow." Mingrun, it's time to practice your archery, there's a pheasant I hit. ”

Su You said: "A gentleman fights wits but not strength, and catching prey traps is much more reliable than bows and arrows. ”

Chen Wei sneered: "You can't eat grapes and say that grapes are sour." ”

Then I saw the group on the hill returning, each with one or two pheasants hanging from their waists.

The captain walked up to Su You, untied the pheasant around his waist, and respectfully put it on the ground in front of Su You.

The rest of the team members did the same, their faces full of admiration.

The pheasants were tied with straw rope with their wings and feet, and they kept fluttering on the ground, but they were all alive.

Chen Yu didn't expect Su You to slap his face without saying a word, so he quickly changed the topic and said to the team leader: "Ah, you are not serious when you are on duty......

Ah Mi sneered and laughed: "Scholar, don't make trouble, that's the harvest of the hunting array laid by my younger brother, and they are just responsible for putting it away when they go down the mountain." ”

Su You took a silk coil from the hand of a native soldier: "This is a living trap, birds have roads and beasts have roads, as long as you find the chicken hall, set up a door word array at the exit, simulate the rooster cry to attract them to rush to the hall, as long as one is caught and struggling, it will be shocked that the rest of the pheasants scatter, have stepped into the surrounding traps, run two steps on the rope sleeve will be tightened on the legs, caught are alive." ”

Chen Wei was surprised: "Where did you learn these weirdness?" ”

Su You smiled: "Don't forget that I am a country child, and the people in the village are good at doing this!" ”

After speaking, he put his fingers into the circle and closed them one by one: "But in addition to what I said above, there are a few tricks, one is that the rope loop needs to be padded on a few small bamboo sticks, a certain height away from the ground; The second is that the season should be right, the chickens gather in flocks and love activities; Third...... The noose needs to be thin and strong enough to be dyed so that the pheasants can't tell it. This kind of silk thread is a product of my sister-in-law's workshop, and I can't find it outside. ”

After speaking, he handed over to a native soldier: "This native soldier brother is a hero, if he hadn't blown the bamboo whistle last night, which was exactly the same as the pheasant crowing, I wouldn't have remembered it, and I wouldn't have such a good harvest today." ”

The native soldier scratched his head and smiled innocently.

Chen Yu rolled his eyes: "I will be cheating and playing tricks, hurry up and adjust the seasoning, and see how to get dinner!" ”

Dinner is actually very simple, the muntjac shelf is boiled in miso soup, the ginger and garlic are heavy, and the meat is cut into thin slices and shabu-shabu. The pheasant is chopped into small pieces, mixed with good flavor and fried until it is crispy, mixed with crispy soybeans, not only has a dish for dinner, but also has a snack on the road tomorrow.

For the rest, the fish tube is enough.

After eating, Su You began to measure the distance from the camp to the Jiangxin boat with Li Lianzhu.

The measuring tool used for the test is very simple, a bamboo tube is dipped in the front of a needle, and several turns of iron wire are wrapped around the middle of the bamboo pipe, and then screwed together, and the iron wire is inserted into the center of a large number of horns.

Then tie a bamboo pole into a tripod, and nail a wooden plate at the upper end to place the protractor.

Take a tape measure, measure out a rope of twenty meters, straighten it on the river beach, and nail it with wooden nails at both ends.

The center of the rope is at a bamboo pole stuck in the camp.

Then put a shelf on top of a wooden peg and place the protractor to ensure that the line on the bottom of the protractor coincides with the line on the ground.

This step is very simple, glue a silk thread to the bottom side of the protractor, drop a small screw, and then rotate the protractor until the two silk threads hanging down just touch the rope on the ground.

After the equipment is placed, adjust the rotating bamboo pipe, and when the mast in the center of the ship can be seen through the round hole of the bamboo pipe, record the angle of the protractor pointed by the pointer on the bamboo pipe.

Then switch to another point and record the angle in the same way.

After returning to the camp, I took out a notebook and a ruler, a small protractor, drew a miniature, and after the angle conversion, the problem became a problem of knowing the three points on the bottom edge of the triangle, that is, the bamboo pole in the center of the camp, and the distance between the two wooden nails, as well as the angle between the left and right angles, and finding the distance between the center point of the bottom edge of the triangle and the vertex of the triangle.

This problem is easy to solve with a trigonometric table, but Li is not able to tie it up yet, and the trigonometric table has not yet been measured.

Su You turned this problem into a similar triangle problem, measured the length of the bottom edge of the triangle on the drawing, and the distance between the center point and the vertex, plus the condition that the length of the bottom edge of the triangle was 20 meters, and calculated the distance between the camp and the big ship according to the proportional relationship.

This rough instrument is actually the working principle of the theodolite or collimator, and this set of measurement methods is actually triangulation.

As early as 600 years B.C., the Greek philosopher Thales measured the length of his own shadow and that of the pyramid, as well as his height, and used the principle of resemblance to measure the height of the pyramid, the distance between himself and the ships at sea, and the height of the overhang.

In China, more than 200 years ago, the cartographer Pei Xiu also mastered this method.

Liu Hui, a mathematician at that time, proposed a calculation formula, assuming that two ships on the sea surface are in a straight line with the island, knowing the distance between the two ships and the angle of the ship's observation of the island tip, and calculating the projection distance from the ship to the island.

This method should not be underestimated, it is the basis of cartography.

With angle rulers, thread fine-tuning technology, bubble tubes that can be made from glass tubes, and observers, a simple theodolite can be made.

If you have to be more true, the difference is only a telescope and a correction formula for the curvature of the earth when measured at very long distances.

However, even if there are no two of these things, it is possible to correct this problem by making a large-scale survey based on a large-scale survey and building a triangulation network and a triangular lock, and a very accurate map can be obtained.

Su You didn't plan to do this by himself, his task was just to develop the theodolite, and then give the theodolite to the guys of Sitong Trading and their business partners, and they would complete it.

In addition to data recording, there will also be a lot of mathematical knowledge involved here, and opening squares and squares are basic.

However, in today's Great Song Dynasty, in addition to Su You, a traverser, there are not one or two people who know this, and the method of increasing and multiplying that Su You will know, it is ashamed to say that it was invented by the mathematician Jia Xian at this time!

We can't underestimate the mathematical level of the people of the Song Dynasty today, Jia Xian gave the "method of opening the lock by establishing the solution", and then proposed the "method of increasing the multiplication of the party to seek incorruptibility", and gave the sixth-order Jia Xian triangle to explain the connection between the powers.

The discussion of the Pythagorean problem is based on the "Pythagorean Thirteen Diagrams" and then the solution of the problem, which is completely a clear system.

Such a math master, because he did not study Liu Wei's fractions and calculating the differential number that is, the limit theory field thoroughly enough, it is more likely that he omitted Jane in the book for the sake of conciseness, and was severely criticized by his junior brother Zhu Ji: "Abandon the remaining points, and the reason is not finished"!

They are the Xie Ears of the Great Song Dynasty today!