Geological compass and geomantic compass

Compass is called compass, which was created in the era of Xuanyuan Huangdi, and later passed down by the sages of past dynasties. It was revised and perfected by observing the ups and downs of mountains, rivers and plains on the earth according to the principles of Yijing and Heluo. It is used to determine the direction and survey the terrain. Most geologists and sailors call it "compass" or "Luo Geng", but seldom call it "compass". Speaking of the use of the compass, I believe it will take up a lot of space if we discuss it in detail. Because it contains too many things, this article only talks about simple usage. There are many kinds of compasses, such as ternary disk, three-in-one disk, ternary three-in-one dual-purpose disk, easy disk, mysterious disk, and unique disks of users in various schools. However, no matter what kind of compass it is, there must be a layer in the middle that is in the direction of the twenty-four mountains. From the north, they are Renzigui, Ugly Genyin, Jiamaoyi, Chen Xunsi, Bingwuding, Shen, Geng Youxin and Xu Ganhai. * * * Twenty-four directions. If you have a compass, you can find that the relative degrees of the compass and the pointer are as follows: azimuth divination position, 24 mountain angle, due north, Karez deck 337.5-352.5-7.5, 7.5-22.5, northeast, 22.5-37.5, 37.5-52.5, 52.5-67.5, East China. 82.5-97.5 97.5-112.5 thoughts on southeast Chen Xun12.5-127.5142.5 650. 7.5-172.5172.5-187.5187.5-202.5 Southwest Wei Kun Shen Kun 202.5-217.5217.52/. .5 262.5-277.5 277.5-292.5 Northwest trunk, 292.5-307.5-322.5-322.5-337.5 After knowing the direction of the Twenty-four Mountains, let's look at the shape of the compass. As can be seen from the shape of the compass, the center of the compass is a circular Tianchi (that is, the compass used for orientation). Outside is a movable turntable with a copper surface and gold lettering on a black background, which is called an inner disk or dish. The circle on the disk is full of words, and it is customary to call a circle a layer. The first layer has 24 directions, and the outermost layer is a square disk, which is called an outer disk or a square disk. The tray body is made of rosewood, which is the most durable, but its weight is heavier than that of ordinary wooden trays. There are four holes in the outer disk, and two fishing lines or glue lines respectively pass through the holes in the middle of the four sides to determine the sitting posture. Compasses are mainly used for central magnetic needles. The inner plate outside Tianchi Lake is made of steel. The background color of Tianchi Lake is generally white, and there is a red straight line at the bottom. There are two red dots on the left and right of the red line at one end. The red line is located on the north and south sides. One side with a red dot is purple square (due north), and the other end is noon (due south), with a very sensitive magnetic needle on it. There is a small hole at one end of the magnetic needle. When using the compass, hold the outer disk with both hands left and right, and separate your feet slightly. Put the compass between the chest and abdomen, keep it horizontal, not high left and low right, and not high front and low back. Then stand upright with your back as the seat and your face as the direction. At this time, the cross silk thread on the compass should coincide with the front, back, left and right positions of the house. If the crosshair direction is incorrect, the measured sitting posture will deviate. After fixing the position of the crosshairs, move the inner disk with both thumbs. When the inner disk rotates, Tianchi will rotate with it. Turn the inner disk until the magnetic needle stops and coincides with the red line of Tianchi. It is very important that the end of the magnetic needle with a small hole must coincide with the two little red dot on the red line, and the positions cannot be lost. At this time, it shows that the fishing line (horizontal line) sitting in the square intersects with the layers of the inner plate. All kinds of data and information we are looking for are displayed in the area where this fishing line passes through and covers. However, there are ten or twenty layers on the compass. Which floor is the direction of sitting? That's the floor of the 24th mountain. It's near Tianchi. We use the "mountain" in the fishing line direction to indicate the direction, and the "mountain" in the fishing line direction to indicate sitting. For example, children are facing the mountain, and sitting on the mountain is noon, so we call it sitting in the afternoon. Knowing that you are sitting backwards in the house, put the compass in the center of the whole house, and you can find out the orientation (or palace) of the whole house from the sitting direction.