What do dragon sand and tiger sand mean?
Dragon sand and tiger sand are Feng Shui terms. Ancient people discovered that the ground and underground water have different compositions in different regions. Water containing specific compositions nourishes the local soil for a long time.
The mineral composition of the soil reaches a special ratio, which will form an environment that is extremely suitable for animal and plant life. This special soil was originally called Longsha. Ancient people even used such soil as medicine to treat diseases.
Through practice, ancient people discovered that this special soil is extremely nourishing for the growth of animals and plants. Therefore, they believed that it could bring wealth and other good luck to people. This led the ancient people to search for useful soil based on some topography and animal and plant characteristics. The area of Longsha.
Extended information:
Determination of Longsha
After long-term summarization, the ancients found the general direction of Longsha, in order to confirm whether the soil was "Longsha" "Sand", the final conclusion will be based on the phenomenon called Tai Chi halo.
The ancient people's search for Longsha was considered a major event for the tribe or the country, so they would hold rituals such as sacrifices. These rituals were performed with pious hearts. In modern science, these ritual performances can be It makes no sense to call it a stage play. But there is one mitigation that is scientifically sound, that is, the sacrificer burns a substance called a seal book together with the soil.
The seal book is a scroll made of bamboo and wood, with seals on it. The seal ingredients are a mixture of various plants and minerals. (For details on the seal configuration method, "Book of Yin and Yang of the Tang Dynasty") This substance will react chemically with soil components called "Longsha" at high temperatures.
The ashes formed will look like stone but not stone, like soil but not soil. When rubbed, it will look like powder, and there will be circles of patterns like tree rings, which ancient people called Tai Chi halo. There are detailed descriptions of the phenomenon after burning in ancient documents:
Zhao Yuandu's "Acupoint Jue": "Looking from a distance, there is something, looking close, there is nothing, looking sideways, it is exposed, and looking directly, it is blurry. All are good in Tai Chi. "It's so subtle."
Xu Shanji's "Instructions for Women: Acupuncture Methods": "Seeing a round halo between the faint and hidden moisture is called Tai Chi halo.
If the soil does not have special characteristics. The "Dragon Sand" containing the ingredients will not cause the above phenomenon. According to the "Oriental Knowledge Record", in ancient times, in order to make the Tai Chi halo phenomenon more obvious and accurate when holding the above-mentioned sacrifices, something called Dharma Salt was added. (For details on the preparation method of Dharma salt, please refer to "Yin Yang Book of the Tang Dynasty")
Baidu Encyclopedia-Longsha