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Those who ask for it, the main expenses are for the needs of making a living, the resources of skills and courtesies.
The needs of making a living, everyone depends on things to survive in the world. If the craftsman wants to make utensils, he needs the cost of materials and tools; if the merchant wants to trade and move, he needs the accumulation of capital; if the farmer wants to cultivate crops, he needs to grow grain and agricultural tools. If there is no such thing, it is difficult to maintain a livelihood, so he needs it to survive. For example, as recorded in "Tiangong Kaiwu", potters need mud and kilns to make pottery. If there is no such thing, the pottery industry will be wasted. It is necessary for making a living, which is a major reason for finding things.
The resources of skills, the ancient craftsmen and scholars all strive to improve and benefit from skills. If you want to refine your business, it must be useful. The healer seeks herbs to test prescriptions, the painter seeks paints to touch up the color, and the swordsmith Suoliang iron to refine the blade. The essence of skills is related to fame and livelihood, and is also the foundation of inheritance and innovation. For example, all kinds of skills in "Tiangong Kaiwu" depend on the craftsman to seek exquisite things before he can improve. If there is a lack of required materials, the skills are stagnant and not advanced, which is the sublimation of the art.
The service of courtesy and righteousness, Huaxia values courtesy and righteousness. In weddings and funerals, there are rituals, and things need to be used as courtesies. Sacrifice to ancestral temples and gods also requires offerings and sacrifices. Courtesy and righteousness are the foundation of the world, and if they are lost, people will be confused. Therefore, ask for things from them to perform courtesy and righteousness. The exchange of relatives and friends, the gift of things, is also an act of courtesy and righteousness. For example, although "Tiangong Kaiwu" does not elaborate on this, the matter of courtesy and righteousness runs through the lives of the ancients. Things are the carrier of courtesy and are indispensable, so the search for courtesy is complete.
All these three, the need for survival is related to survival, the capital of skills is related to development, and the service of courtesy is related to human ethics and rules. All are the main uses of those who ask for it, and none of them are indispensable. They all have a crucial position in the lives of the ancients.

Ask him what common production methods he knows? Answer: There are many kinds of production methods, and I will briefly describe the common ones today.
One of them is the method of agricultural mulberry. Agriculture is related to the planting of grains. In spring, choose good seeds, whole the field, and sow grain seeds. Till the soil deeply to loosen the soil and help the seeds take root. And it needs to be irrigated in a timely manner, according to the amount of rainfall in the day, or channel water, or dig wells to get water, moisturize the seedlings. When it grows, remove weeds, prevent pests, and protect it with heart, until autumn. Mulberry is the foundation for raising silkworms. Planting mulberry needs to choose a suitable place, apply fertilizer, and cut its branches to make it lush. There is also a way to feed silkworms. The tender mulberry leaves are picked, washed and dried, and fed on time. After the silkworms form cocoons, silk is reeled and woven. This is the general strategy of agricultural mulberry production.
The second is the method of smelting and casting. For an iron caster, iron ore is first mined, and the quality is selected. The ore, coke, limestone, etc. are placed in the furnace. Blast in a bellows to raise the temperature of the furnace. The ore is smelted at high temperature, and the molten iron flows out to remove impurities. Then, the molten iron is injected into the mold, and swords, plows and other utensils are cast as required. After cooling and forming, it is sharpened to make it sharp or smooth.
The third is the method of hand weaving. If weaving cotton cloth, first flick the cotton to make the cotton wool Cotton is spun into cotton yarn on a spinning wheel, and then the cotton yarn is woven on the machine. Weavers weave all kinds of cotton cloth according to patterns and techniques, shuttle leads, interweave warp and weft, and weave all kinds of cotton cloth. If weaving silk is more complicated, from the cocoon twisting, through silk reeling, winding and other processes, and then carefully weaving, you can get exquisite silk.
The fourth is the method of brewing. Take winemaking as an example, choose the best grains, such as sorghum, wheat, etc. Cook the grain first, let it cool, mix it with koji, and put it in a tank for fermentation. According to the type of wine, control the fermentation time and temperature. After fermentation, the wine is obtained by distillation, and after aging, mixing and other steps, it finally becomes a fine wine. Vinegar also has its own way, using grain as raw material, through saccharification, alcoholic fermentation, acetic acid fermentation and other processes, to obtain sour and mellow vinegar.

Hidden in the warehouse, transported in the world, all things in the meantime must be paid attention to.
When storing in the warehouse, the first place should be selected. The warehouse site should be high and dry, avoiding water and moisture, to prevent the hidden things from being wet and rotten. And it should be strengthened and its walls should be strictly guarded to prevent small coveting and theft. The hidden items in the warehouse must also be classified and placed in a well-organized manner, which is easy to use for analysis. Every time a new item is put into the warehouse, its name, number, quality, and date of storage should be recorded in detail; when the old item is out of the warehouse, it should also be recorded in the same way, and the number of stocks should be clear at a glance.
When transporting, it is important to be cautious. Depending on its texture, the goods shipped are properly packaged. Those who are fragile should be lined with soft objects to prevent earthquakes and collisions; those who are valuable should send more guards to take strict precautions. During the itinerary, observe the weather in detail, and seek shelter in case of wind and rain to avoid its damage. And when planning the path, choose a smooth and convenient way to avoid damage due to rough roads. It is also necessary to make three rules with the escorts, so that they will perform their duties and not slack off. If there is any negligence, they will be severely punished.
Furthermore, storage and transportation are both related to current luck. When the situation is judged, the needs of the market are observed, and the rise and fall of prices are expected. Profit can only be made when the goods are stored and transported at the right time. If you are ignorant of the current situation, if you hoard improperly, or if the transportation is not timely, you may cause damage to the property and miss the opportunity.
All matters of storage and transportation must be handled with care, attention to details, and caution in order to ensure that the hidden and transported items are safe and everything goes smoothly.

Mercury is also a highly toxic substance. It has a great impact on the environment and human health.
Looking at the environment, once mercury is released into nature, it may flow in water, disperse in soil, or escape from air. In water, mercury can be converted into methylmercury through complex biochemical reactions, which is especially toxic. If aquatic organisms ingest it, mercury accumulates in their bodies and accumulates layer by layer along the food chain. For example, small fish eat mercury-containing plankton, and large fish eat small fish, the concentration of mercury in the body of large fish gradually increases. In this way, the balance of aquatic ecosystems is greatly disrupted, and the survival and reproduction of many aquatic species are threatened. In soil, mercury can affect the activity of soil microorganisms, hindering their decomposition and transformation of organic matter, causing soil fertility to decline and soil quality to deteriorate. As for the atmosphere, mercury can be transported over long distances with airflow, diffuse to distant places, and then settle, return to soil and water bodies, and circulate to harm.
As for human health, the harm of mercury should not be underestimated. If a person inhales mercury vapor through breathing, or ingests mercury-containing substances through diet, mercury will enter the body. Mercury easily combines with thiol groups of human proteins and enzymes, disrupting the normal metabolism of cells. In the nervous system, it can cause dizziness, headache, insomnia, memory loss, etc. In severe cases, it can cause tremor, ataxia, and even mental disorders. Mercury also has serious damage to the kidneys, which can cause abnormal kidney function, and symptoms such as proteinuria and hematuria are common. If pregnant women are exposed to mercury, mercury can penetrate the placenta, affect the development of the fetal nervous system, and cause serious consequences such as fetal malformation and mental retardation.
Therefore, the harm of mercury to the environment and human health is deep and huge, and it should be handled with caution to prevent it from becoming a disaster.

In today's city, if you want to understand the trend of its development, you should look at all the ends.
When you first look at the sky, the prosperity of the city often depends on the luck of the times. In a prosperous age, the government is well-connected and the commerce is prosperous, and its development is smooth. Like the ancient Tang Dynasty, the four seas came to the dynasty, the city of Chang'an was bustling, and the general merchandise gathered. This is the time of the day to help it prosper. And in this world, science and technology are new every day, and policies are more profitable. If you can take advantage of the times to take advantage of the situation, attract new industries, and use advanced techniques, the city will flourish.
Second look at the geographical location. In the land of the city, the transportation is convenient, the goods flow smoothly, and people gather in the city. Those who are on the river and sea are conveniently connected to the inside and outside; those who are on the main road are connected by cars and horses, and merchants gather. In the past, Yangzhou, due to the benefit of the canal, was rich in the world, and the city was prosperous. Today's cities, if there are railways, high-speed vertical and horizontal, airports and seaports, the foundation of their development will be solidified.
Re-examine people and people. The rise and fall of the city, the strength of the people is at stake. Business people are based on integrity, diligence is essential, and their reputation is strong and visitors are always there. The people are happy to work, have the courage to innovate, can come up with good strategies, make good products, and the city will prosper. And the government and the people cooperate, and the government is good and business is smooth, creating a good environment for the development of the city.
If there are unique products in the city, such as Suzhou embroidery and Huimo, which are unique and charming, they can attract customers from all over the world and expand the city far away. Or there are other kinds of scenery, such as the ancient city of Lijiang and the ancient city of Pingyao, which gathers people with scenery and brings alive commerce.
The development of a city is in line with the time, geographical location, and people, and its characteristics, so that it can flourish and prosper in the long run.