Mercury, or mercury, is the only metal that is liquid at room temperature, and has unique characteristics among the many substances involved in "Tiangong Kaiwu". Its color is silver-white, bright and dazzling, and it does not flow, just like a smart spiritual liquid.
Mercury has a high density and is heavier than common metals. If you carry it by hand, you can feel its heaviness. Its texture is smooth, like fat to the touch, and it does not feel firm and brittle. And mercury has good electrical conductivity, which is quite important in many electrical experiments and applications.
Furthermore, the boiling point of mercury is relatively low, only 357 degrees Celsius. It is easy to evaporate when heated, and turns into a gaseous state, which is invisible. This property makes mercury unique in ancient processes such as alchemy and metallurgy.
Due to the relatively stable chemical properties of mercury, it is not easy to react with oxygen at room temperature. However, when encountering specific substances, such as sulfur, the two quickly combine to form mercury sulfide, which is brightly colored and often the choice of ancient pigments.
Jiang sand is also the substance described in "Tiangong Kaiwu". Its texture is hard, the particles are uniform, and it is mostly golden or light yellow, which shimmers in the sun. Jiang sand is chemically stable and resistant to acid and alkali corrosion. It is often used in construction, casting and other fields. And Jiang sand has good thermal conductivity and can be effective in some places where heat dissipation is required.
These two substances, the liquid state of mercury is flexible and volatile, and the solid state of river sand is hard and stable, forming a sharp contrast. They each played an important role in ancient craftsmanship and life, providing diverse possibilities for production and life at that time, and demonstrating the ancient people's understanding of material characteristics and utilization wisdom.

Mercury is a highly toxic metal. It is liquid at room temperature and has a metallic luster. Its chemical properties are relatively stable. In air, mercury does not easily react with oxygen, but under heating conditions, it can combine with oxygen to form mercury oxide.
Mercury can form alloys with many metals, namely amalgams. For example, sodium amalgams, zinc amalgams, etc., which have certain uses in metallurgy and other fields.
Mercury exhibits strong solubility to many metals, and metals such as gold and silver can be dissolved in mercury.
The culprit of Minamata disease is mercury, and its compounds such as mercury chloride and methylmercury are extremely toxic. Methylmercury easily accumulates in living organisms and is passed through the food chain, eventually endangering human health and life in serious cases.
In ancient times, mercury was often used by warlocks for alchemy, and many emperors pursued immortality and took mercury-containing pills, which actually damaged the body.
And mercury is volatile, and mercury vapor is also toxic. Once inhaled into the human body, it will cause serious damage to the nervous system, kidneys, etc.
Mercury in rivers, if it flows into the water body, will seriously pollute the water source. After aquatic organisms ingest mercury, it will accumulate in the body. If humans eat these mercury-contaminated organisms, mercury will enter the human body and endanger health.
In addition, mercury compounds are often used as catalysts or participate in specific reaction processes in chemical reactions, but due to their toxicity, extreme caution is required when using them.

Mercury is a valuable commodity. In ancient times, mercury had many important uses.
Mercury, which is water, is commonly used in: First, it is very important in the pill. Ancient alchemists believed that mercury has magical effects, and they wanted to use it to give birth to an elixir of immortality. Ge Hong's "Baopuzi" describes the method of using mercury and other things to make pills, "Dan sand is made of water, and then it is made into Dan sand", which is the weight of mercury in the ancients. Second, it is also useful in the field. The "Divine Materia Medica" is listed in mercury, which can be used to treat skin diseases such as scabies. Third, in terms of tombs, the ancients obtained mercury to prevent corrosion, such as Qin Shi Huang's mausoleum, which used water to cover hundreds of rivers, rivers and seas, in addition to creating grand landscapes, or it also meant using mercury for anti-corrosion.

, First of all, it is widely used in manufacturing. Ancient manufacturing is multi-purpose, such as the fifth generation, because it is cheap and easy to manufacture. In addition, it can be used in the manufacture of various utensils, such as tripods, tripods, etc. Secondly, in terms of construction materials, the ancients used powder as a material. The powder used in feminization can make the color white. Furthermore, in terms of construction, it is often used in waterproof pipes for houses because of its anti-corrosion properties. In ancient times, some houses were built with boards to prevent rainwater leakage, and some water conservancy projects were also built with pipes.

There are many ancient methods for making rods and arrowheads, and each has its own subtlety.
One of the methods for making rods requires choosing good materials. Often take tough wood, such as sandalwood, peach wood, etc., which is hard and resistant to corrosion and can be used for a long time. First, use an axe to cut the wood as the appropriate length, and then use a planer to cut its outer skin to make the surface smooth. Then, use a chisel to cut holes in the wood according to the desired shape. The size and depth of the holes depend on the use. If it is for water extraction, the holes should be large and deep to accommodate more water; if it is for irrigation, the holes can be slightly smaller and shallow to allow water to flow slowly. After making, or apply tung oil to prevent moisture, or engrave patterns to increase its appearance.
Second, bamboo can also be used. Choose a sturdy bamboo, cut off both ends, and keep one end of the bamboo joint. Use a sharp blade to open the hollow part of the bamboo, and then drill a small hole in the bamboo joint, or open a long groove on the side of the bamboo body. Bamboo is light and easy to carry, and it is convenient to obtain materials. It is often used in mountain forests and water towns.
As for making arrowheads, the first choice is iron. Good iron is tempered to remove its impurities and increase its toughness and hardness. First heat the iron to red, and beat it with an iron hammer to make it formed. The shape of the arrowhead is pointed and wide-winged. The pointed head is conducive to wearing things, and the wide-winged wings can fly steadily. When beating, you need to pay attention to the symmetry of the arrowhead to make the flight balanced. Wait for the prototype of the arrowhead, and then trim it with a file to make the arrowhead smooth and sharp. Finally, or quench it in water to greatly increase the hardness of the arrowhead. However, when quenching and the water temperature are exquisite, it needs to be tested repeatedly to get a good device.
There are also people who use bronze to make arrowheads. Melt the bronze in a crucible, wait for it to turn into a liquid, and pour it into a special fan. The shape of the fan is made according to the shape of the arrowhead, wait for Bronze arrowheads were often used by the military in ancient times. Their color is simple and their quality is also strong.
All these methods of making arrowheads and arrowheads are the crystallization of the wisdom of the ancients. Although the years have passed, their exquisite skills are still worthy of future generations to explore and inherit.

Mercury should be kept in the process of storage, and the general matter should be paid attention to.
Mercury is good in nature and toxic. For storage, it is necessary to use a dense container to prevent leakage. Because it is easy to burn and can cause poisoning in the air, it is necessary to store it in a safe and safe place. It is also necessary to keep the container intact. If there is any leakage, it should be covered with sulfur as soon as possible to reduce the toxicity of mercury sulfide.
The toxicity of the two is slightly less than that of mercury, but it cannot be ignored. It is suitable for storage in a dry place to avoid the tidal environment, and it is easy to grow. The package is firm to prevent its collision.
Furthermore, these three are all expensive, and they should not be stored or stored together with food, water, etc., to avoid the risk of dyeing and endanger the well-being of people. And its operators should not have anti-food devices, such as gloves, masks, etc. After work, they must use their hands to prevent food poisoning.
Therefore, mercury, mercury, and water are all carefully considered to ensure safety and avoid food poisoning.