Compass. Open the door and let the water out. What board is used for vertical positioning?

The earth, people and sky are mainly based on the site, and the sky and people are all around the site and responsible for each other.

In operation, the site is vertical, people look at the sand, and the sky is full of water. To sum up:

1. Infield elevation needle: located at the meridian elevation of the Twenty-four Mountain, it is used to sit on the mountain, stand upright, climb the dragon, and also pull the sand.

2. Needle in the intermediate person's tray: at the back half position (seven and a half degrees) of the normal needle on the site, used for pulling sand.

3. sewing needle on the outer ceiling: it is half a degree (seven and a half degrees) ahead of the site needle, used to receive water and sometimes used to remove sand.

Of course, it is not enough to rely on three sets. For example, vertically, it depends on the distribution of gold and dragons. As for the eight evils, these are basically inseparable.