How to judge the position and direction of the field?
First, use a geomantic compass or compass: place the geomantic compass or compass horizontally so that the bubble is vertically centered. At this point, after the magnetic needle does not move, the gray end marked with n is called the north area. Besides measuring the true north direction, Feng Shui Compass and Compass can also measure the actual direction of an overall target by turning on the standard camera of Feng Shui Compass or the 0 standard ruler of the standard inner diameter gauge, so that the overall target, the 0 standard ruler and the magnetic core are on the same parallel line. After the geomantic compass is horizontally stationary, the standard ruler at the N end is the direction of the general target, and the general target is to correctly measure the northeast 36. Although it is simple and convenient to use Feng Shui compass and compass to identify the direction, we must pay attention to 1. Try to keep the level. 2. Don't get close to magnetic chemicals. 3. Don't mistake the S end of the magnetic needle for the northern region, resulting in the direction deviation of 180. 4. Master the magnetic declination of the theme activity area and correct it.
Second, the use of the sun and the moon: In a sunny day, you can simply understand the eastern and western countries of China according to the sunrise and sunset, and you can also identify the methods, but there is only a general possibility. The correct measurement method is as follows: 1, the measurement time of watches is half that of sunshine, and 12 refers to the northern region. Generally, you can quickly identify the direction around 9 am or 4 noon, and use the direction in half the time. 12 is the northern region, and the noon time is 14: 40, half of which is 7: 20. For the sun, 12 point refers to the northern region, or for watches in the northern region, the time around 12 point overlaps with watches around 1 point, or watches overlap at about 2 o'clock.
Please pay attention to: 1. When judging the direction, the watch should be placed horizontally in the afternoon of 20 30 north latitude, which is not suitable for application. On the basis of the standard production line, increase 1 hour eastward and 1 hour westward every day. 3, shadow measurement sunny days, erect a stick on the ground, the figure of the stick moves with the change of the sunshine department. This shadow is the shortest at noon, and the connecting line at its end is a parallel line. The bisector of this parallel line is the north-south direction. Draw a series of inner circles on a 50×50 cm map. The radius of the circle in the same boat increases to 1 cm. Nailed to the tablet computer and fixed horizontally. Insert the thin needle and the needle with the length of 12- 15 cm vertically into the center point.
When the sun changes, the nodes of the body always pass through the inscribed circle. Mark this point, then connect two parallel lines on the same circle, and connect the center of this parallel line with the center point. This line is a north-south line, and the arc top direction is the northern region. 3. Directionality of the sun and the moon: The sun sets in the east, and the general directionality can be seen by observing the sunrise and sunset. It can also be measured by the following methods: for a vertical straight bar (height exceeds 1 m) on the flat ground, mark the top of the straight bar (put stones, etc.) first. ), and the body of the straight bar moves with the movement of the sun. After 65,438+00-65,438+0 hours, mark the top of the stick, draw parallel lines between the two marks, and draw a vertical line between the parallel lines. This cross is
Third, using the night star, you can tell the direction according to the Big Dipper and the Southern Cross. 1, Big Dipper, at night, under the starry sky with dark stars on the moon, people will always look for a big Dipper constellation near the spoon. Which spoon has the brightest star seven times farther away, that is the Big Dipper, which is due north, and clockwise is the East, South and West. The Big Dipper is located in the sky due north, and its aspect ratio angle is equal to the horizon, so it can be found quickly. Generally speaking, according to the Big Dipper (Ursa Major) or the W Star (the twelve constellations after the Fairy), the Big Dipper is seven bright stars that look like spoons. The two β's of the spoon are connected to α, and the Big Dipper is magnified about five times. When you can't see the Big Dipper, you can look for it according to Star W, the twelve constellations of Hou Xian. The twelve constellations of Hou Xian are composed of five bright stars, which look like W English characters. The opening direction of English characters is about twice the opening width, which is the distance of the Big Dipper. 2. The Southern Cross is located at the southern end of latitude 23 30'. At night, you can see the Southern Cross, which is composed of four bright stars, like a cross. In the lower right corner, four and a half times the length of the line from γ to α (no stars) is due south.
4. Using the contour lines and the characteristics of green plants, the contour lines and the growth characteristics of plants in suburbs are good orientation representations, and improving the professional knowledge in these areas is helpful to quickly identify the direction. 1, contour features, house: generally the door faces south, in the north of China, especially the temple: generally the door also faces south, especially the temple, emphasizing contour lines: bryophytes with low growth and development are likely to be wet and cold north tips. 2, plant growth characteristics, generally shady slopes, that is, northern slopes, dwarf chlorophytum and lianas grow and develop more than sunny slopes. A single green plant is lush in the sunny side, and there is a great possibility of moss growing in the shade to the north. In the north of China, there are many tree rings with clear cross sections, sparse rings in the south and dense rings in the north. Bamboo stems are south, green bamboo stems are north, and the color is yellow.
5. Map orientation and map orientation: The topographic map orientation of most areas is the upper north, lower south, left west and right east of the engineering map, so it is very important to have a correct understanding, which is a subject that must be clarified in the itinerary arrangement of the theme activities of the scheme.
Six, using the shadow observation method, find a stick to stand in the middle of the watch, rotate the perspective of the watch, so that the stick and the second hand coincide. At this time, the middle point of the included angle between the second hand and several directions is north, and the other end is south. In addition, the line can be marked, which is conducive to the return of the original road. You can tie a red cloth strip to a tree to attract attention, or you can mark it with stones.
Seven, use the watch to identify the direction, the earth rotates 360 degrees at a constant speed in 24 hours, 1 hour rotation 15 degrees. The second hand of a watch is always twice as fast as the sun. The basic principle can be roughly measured by watches and sunlight. At 6 o'clock in the morning, the sun is in the east of China, and the shadow is biased towards the western countries. At this time, the second hand of the watch is biased towards the sun, and the word 12 on the case is biased towards western countries. If the watch case rotates 90 degrees, the word 3 of the watch case faces the sun at 6: 30, and the word 12 is in the north area in the afternoon 12, and the sun is in the south area 12: 30. If the word 6 of the watch case is facing the sun, the regional time difference should be considered when measuring the azimuth angle in this way. Beijing time should be converted into regional time. Based on the longitude line 120 degrees, the longitude and latitude are east longitude 15 degrees, China Beijing time 1 hour, west longitude 15 degrees, China Beijing time 1 hour, that is, on the spot. The latitude and longitude of Urumqi is 87 degrees and 40 minutes, (120-87) ÷ 15 = 2 hours and 9 minutes, China Beijing time minus 2 hours and 9 minutes, which is the local time in Urumqi.
The above two methods are not applicable in summer in Chiayi, Taiwan Province Province, China, Nan 'ao Island in the northeast of Shantou, Guangdong, Yulin City, Guangxi, and the southern end of the Tropic of Cancer in the old city of Yunnan (23 degrees and 27 minutes north latitude).
By the way, we know the basic principle of the relative position motion 15 between the earth and the sun when the earth rotates at a uniform speed, which can be roughly measured by watches and sunlight. Instead, you can use a compass and sunlight to measure the approximate time. The way is that the north needle points to the north fixed item, and the reading value of sunshine direction 15 can be divided. In China, based on China-Beijing time, Beijing is on the economic network of 120, and other regions must make various adjustments according to the differences of latitude and longitude.