What is solar cold water?

The ancients advocated using natural phenomena and being good at taking images and analogies. The cold water of the sun can be understood as 1, and the meridian of the sun is the main water, which is easy to understand and recognize. 2. Why is it called cold water? It turns out that water comes from the combination of water vapor in the sky, and the water vapor becomes rain, and the upper air naturally cools down. Therefore, the meridian dominated by the sun meridian is a process from cold to water, so the function of the sun meridian is called "cold water of the sun" for short or synonymous with the meridian.