Compass, also called compass, is the main tool of geomantic omen. It consists of three parts:
First, Tianchi
Also known as the bottom of the sea, it is the compass. The Tianchi of the compass consists of thimble, magnetic needle, submerged wire, cylindrical outer box and glass cover, which are fixed in the center of the inner disk. There is a sharp thimble in the center of the bottom surface of the round box, and a concave hole in the center of the bottom surface of the magnetic needle, and the magnetic needle is placed on the thimble. The arrow of the compass points south at one end and north at the other.
There is a red line at the bottom (seabed) of Tianchi Lake, which is called the submarine line, and there are two red dots on both sides of the northern end. When in use, it is necessary to make the northern end of the magnetic needle coincide with the seabed line.
Modern compasses mark the crosshairs on the seabed. When in use, the northern end of the magnetic needle should point to the northern end of the reticle, and the magnetic needle should coincide with the north-south line of the seabed.
Second, the inner disk
It's the turntable next to the compass. Many concentric circles are printed on the inner disk, and one circle is called a layer. Each floor is divided into different equal parts. Some floors have more squares, while others have fewer squares. The least floor is divided into eight squares, and the most floor has 384 squares. Different characters are printed on each grid. There are many kinds of compasses, some with many layers, some with few layers, the most with 52 layers, and the least with only 5 layers.
The contents of the compass are printed on different circles (layers) of the inner disk, which is the main component of the compass. All feng shui schools put the main content on the compass, making China's compass an encyclopedia of China's skills.
Third, the outer disk
The outer disk is square, which is the tray of the inner disk. There is a small hole at the midpoint of the outer side of the four sides, and the red line penetrates into the ten meridians of Tianxin, which is used to read the contents of the inner disk. The ten directions of Tianxin are required to be perpendicular to each other, and the new compass you just bought must be calibrated before use.
Compass is a basic tool to measure the magnetic azimuth of the earth's surface, which is widely used in military, navigation, surveying and mapping, forestry, exploration, construction and other fields.
The main function of compass is to measure orientation, and the positive needle of the station points to the meridian direction of the earth's magnetic field. Since ancient times, people have used compasses to measure directions, which is also the origin of due south and due north. As the most basic application of compass, it is mainly used to measure local magnetic field. In the introductory knowledge of Feng Shui, we can know that different hands of the compass have different functions, not only representing the direction, but also representing the angle and so on.
It is not difficult to see from the shape of the compass that this is a round object, representing Tianchi, which is what we often call the compass. The outside of compasses is generally copper, and most compasses have gold characters on the bottom, which is called the inner disk. There will be many words on the disk, divided into several layers. One layer represents twenty-four directions, and the outermost layer is square, which is called a square disk. Different compasses are made of different materials, among which rosewood is the most durable, but it is also heavier.
Compasses have four holes on the outside, which are fixed with fishing lines or glue lines, and are often used for shaping. The most useful part of the compass is the magnetic needle in the middle. The inner plates outside Tianchi Lake are mostly made of steel, and the color of the bottom surface is generally white. A red straight line is often drawn below, with a dot at one end and a red line on it. When using a compass, you usually use it with both hands. At this time, you should separate your feet slightly and put the compass on your chest, so as to keep the compass level and avoid the imbalance before and after or left and right.
In practical application, it is necessary to overlap the fishing line on the compass with the four directions indoors. If there is deviation due to inaccuracy, it is difficult to get accurate measurement results. After fixing the direction of the crosshairs, turn them with your thumbs. When the inner disk starts to rotate, the Tianchi in the middle will also rotate with it.