Do everything according to your ability, whether it is a person, a family, or even a country, you must not consume too much of your own energy, otherwise it will cause very serious losses and cause very bad consequences.

If a person is overworked, it will seriously wear out his body and make his body less healthy, a family will bear an unbearable burden, which will cause the collapse of the family, and if a country consumes too much strength, the country will disintegrate and perish.

The strength of the state includes financial resources, people's resources, material resources, etc., the collapse of finances is the most terrible, the state finances are out of money, the officials of the imperial court will not receive salaries, the army will not receive military salaries, and after a famine, there will be no money for disaster relief.

If the officials can't get the money, they will use the power in their hands to exploit the people, making the people's lives more difficult, and if the army can't receive military salaries, there will be mutiny, or even go directly to rob, go to the mountains to become bandits, and in areas where famine occurs, if you can't get the help of the imperial court, there will be a large number of dead people, and even large-scale peasant uprisings, which will cause chaos in the whole society and let the dynasty collapse step by step.

People's power refers to the people's human, material and financial resources, excessive consumption of people's power, refers to the endless requisition of the people to serve in labor, so that the people are exhausted, with harsh taxes to rob the people's property and goods, so that the people become nothing, difficult to survive, so that the court does not agree, and even rises up to launch a large-scale resistance movement.

Material resources refer to all the materials that can be used, there is a good saying, the soldiers and horses have not moved the grain and grass first, a large army of levies, the consumption of materials is very huge, and as the war enters a state of stalemate, the consumption of materials is greater, if the country's material supply is not available, it is easy to cause the collapse of the army, and then cause the demise of the empire.

In short, human, material, and financial resources are the foundation of an empire, which is very much to be cherished, and must not be consumed too much, otherwise, once it is beyond its means, an empire will collapse.

There are too many such lessons in history, the Umayyad Dynasty is still in a state of expansion at the end of the dynasty, and the same is true for the various dynasties in China, the Great Qin Empire built the Great Wall, built the Afang Palace, vigorously developed Lingnan and other behaviors, resulting in a great loss of national strength, the Great Sui Empire is the same, digging the Grand Canal, three expeditions to Goryeo and other crimes are known throughout ancient and modern times, the Ming Empire due to the accumulation of generations, to the end of the generation, just the lazy royal descendants are as high as hundreds of thousands, these people don't need to do anything, However, the imperial court had to spend money to support them and let them have no worries about food and clothing, which added a great burden to the imperial court's finances and made the imperial court's income and expenditure gradually unable to make ends meet.

The lessons of history must be learned, now the national strength of the Tang Empire is getting stronger and stronger, but it must not be excessively consumed, fortunately, the increase in the current expenditure of the Tang Empire is far from catching up with the increase in income, the money in the treasury is not only not reduced because of the substantial increase in expenditure, but has increased a lot, the original warehouse can not be loaded, so it has to be rebuilt in the imperial city to build a larger warehouse, the scale of the left and right treasures of the imperial city have expanded several times, if the income continues to increase, Then we have to find a new place in the capital to build another warehouse, otherwise, there will be no place to put so much tax revenue.

In the past, the tax revenue of the Tang Empire mainly came from the tax of agriculture, but since Li An engaged in industrialization and promoted the development of commerce, now, the financial revenue of the Tang Empire, the tax revenue of commerce and industry began to gradually increase, and it has become the absolute majority, and the tax revenue of agriculture has become more and more insignificant, and even, there is no pressure to cancel the agricultural tax of the whole country.

Li An led a huge expeditionary fleet to open up new land, which was a great drain on the financial resources of the imperial court, but Li An also captured a lot of wealth along the way, and by fighting hostile and pirate forces, the Maritime Silk Road became gradually unblocked, at least, for the time being, the number of merchants from Datang to Malacca has increased several times, commerce has become more frequent, and the tax revenue of the southern port city of Datang has also increased greatly, and these revenues will soon recover the expenditure of Li An's fleet formation, in short, It's definitely not a loss.

After casually talking about the situation of the Great Food Country, Li An took his civil and military officials to inspect the nearby city wall, because there were 6,000 troops put into the ranks of work, so that all the projects were progressing quite smoothly, especially the construction of the city wall with low technical content.

Because the walls were only two thin brick walls, filled with earth in the middle, there was no difficulty in building them, and the earth was dug up nearby.

The excavation site is five steps outside the city wall, so that after the city wall is built, a natural moat is formed in the place where the earth is taken outside, and as long as the water flow is introduced, then the moat can be formed quickly.

The construction of the city wall, along with the construction of the moat, can be said to kill two birds with one stone, and the prerequisite for doing all this is sufficient human resources.

After the construction of thousands of troops, the work of extracting and compacting the earth was done, the work of building the wall was done by skilled craftsmen, and the most extensive work of taking and compacting the earth and landfill was all done by these soldiers.

In order to speed up the progress of construction, the construction of the city wall was completed as soon as possible, and some machinery was used at the construction site, such as the excavators belonging to the Datang military, these excavators dug a shovel to dig a lot more soil than dozens of soldiers dug, in addition, the dug soil, if it is carried by manpower is also very laborious, the smart craftsman immediately thought of a good way, made a simple conveyor belt, dug soil directly into the conveyor belt, manpower stepped on the conveyor belt, the soil was sent between two thin walls, Then the soil is pushed by man or machine to the place where it is needed, compacted by foot, and finally compacted by machine.

A large amount of manpower, a small amount of machinery, and the ingenuity of craftsmen, these combined, so that the construction period of the city wall was shortened a lot, almost one day, in just one month, most of the city wall was built, and it is estimated that it will be completed within ten days without pressure.

Among them, there is a section of the city wall that has been completely completed, that is, a city wall at the north gate of the city, and this section of the city wall was not built at the earliest, but it is the earliest section of the city wall to be completed.

This part of the city wall was built at the fastest speed, not because of the good geographical location, nor because the craftsmen here worked harder, but because Li Ang attached the most importance to this section and mobilized more craftsmen, so it was natural that the construction could be completed at the earliest.

The outside of the city wall is bare, but in the inside of the city wall, there will be a ladder that allows people to climb the city wall at intervals, and there is one ladder on the left and right sides of the city gate, which is also the largest and widest ladder, and the ladders in the rest of the city are relatively simple and small, as long as they can meet the needs of soldiers to climb the city wall.

Around the edge of the inner city wall, there are also a lot of houses, these are prepared for the soldiers guarding the city wall, the soldiers can rest in these houses in peacetime, once in case of emergency, the resting soldiers can quickly reinforce the city wall, and some houses are stored in the city defense materials, such as swords and arrows, rolling wood, stone these materials, and more large city defense equipment, if it is placed on the city wall in peacetime, it is easy to be damaged by the sun and rain, and it can undoubtedly improve the life of use in the houses under the city wall.

Li An, with his civil and military officials, soon arrived at the northern city wall and walked up the city wall from the wide ladder at the city gate.

Like the construction of the city wall, the ladder is also made of earth, as long as the outer wall and surface are bricks, the bottom of the bricks is all dirt, but because it is compacted, there is no need to worry about damage to the ladder.

The most feared thing about the soil is the rain, because the rain can wash the soil away, so in order to prevent the mud under the city wall and stairs from being washed away by the rain, all the bricks are coated with cement materials, and the coating is very uniform and meticulous, without the slightest leakage, so that the rain will not enter the bottom of the bricks, and will not break the foundation under the bricks.

The bricks were laid very neatly, and it was very comfortable to step on them, Li An felt it, and was very satisfied, and walked to the top of the city wall step by step.

The bricks on the ground at the top of the city wall are laid very well, and it makes people have a pleasing feeling when they see it, the female wall is a short wall on the outside, with a shooting port and a lookout, and there are also small walls inside, however, because the enemy is outside, so, the small wall built inside is very low, only half a person high, and even half the height of the female wall is not even half the height, standing on the city wall, you can easily see all the situations in the city, but if you want to see the scenery outside the wall, you have to go through the lookout and the shooting port, because the height of the female wall is higher than the height of people, will block people's view.

Li An walked to a lookout and looked out, just to see the cement pavement outside, and the craftsmen who were working on one side, the cement road was already usable, so that the foundation on the other side also began to pave the cement road, using the cement produced by the cement workshop in the north twenty miles, so that the nearby materials, the speed and cost of construction will be very favorable.

The top of the city gate is naturally the city gate tower, since ancient times, where there is a city gate, it is generally necessary to build a city gate tower, one is more beautiful, from a distance to see the past is more domineering, the other can also be used for the captain of the city to rest, so that the officers and soldiers guarding the city have a place to take a cool, and the most important reason is because the city gate is the weakest part of the city defense, and the foreign enemy captures a city, generally starting from breaking the city gate, so the defense of the city gate position has always been the most important, Defensive measures are naturally more than the city wall, in addition to the female wall to deploy soldiers and horses, the city gate tower should also deploy troops, rolling wood and stones from the female wall to throw down the killing, and from the high place of the city gate tower to throw down the lethality is absolutely different, the higher city gate tower can give the rolling wood stone higher potential energy, thereby greatly increasing the lethality of the rolling wood stone, to the enemy more deadly attack, if the deployment of archers, from the city gate tower shooting, the distance of the attack and the archer's vision will be very good.

The normal city gate tower is mostly two-storey, but in some important cities or checkpoints, the city gate tower is relatively tall, it can be more than three stories of the city gate tower, or even higher and larger.

Li An does not pay much attention to the defensive role of the city gate tower, and the construction period is relatively tight, so the city gate tower of Anzhu City only has two floors, which is the most common city gate tower specifications, and there is no difficulty in building it.

Most of the ancient city gate towers were built of wood, and how can the strength of wood be compared to that of concrete? Moreover, wood is not fireproof, once a fire occurs, the wooden gate tower will be completely finished, so Li An demanded that the gate tower of Anzhu City must be built of concrete, and even precious steel bars should be used in important load-bearing parts, and the walls should at least be built with bricks, instead of using wooden materials that lack solidity.

"Let's go upstairs and have a look."

Because of the obstruction of the female wall, Li An needs to hook his head to see the scenery outside the city, which is not very good, and this also affects his image, so he decided to go up to the city gate, where there is only a waist-high fence, which will not block his view.

The staircase is wooden, which is very comfortable to walk on, although Ang Lee asks to use concrete materials as much as possible, but some parts are still most convenient to use wood, and besides, the small staircase inside is safe, and there is nothing wrong with using wooden materials, as well as window materials, which are also made of wood, but the walls and themes are replaced with concrete materials.

The tiles on the top of the city gate tower are also ordinary tiles, which are produced by the nearby brick kiln factory, and are no different from the tiles of the other city gate towers.

Walking up to the city gatehouse, Li An stood next to the wooden fence, stroked the waist-high wooden fence with one hand, and raised his eyes to look out of the city.

Since there is no obstruction in the line of sight, Li An can observe the scene outside the city on a larger scale, the cement road outside the city, and the craftsmen who are working, he can see more clearly.

And farther away, you can see a number of hills, twenty miles to the north, bubbling with bursts of smoke and dust, it is obvious that there is a lime mine, and the smoke and dust are caused by the craftsmen mining the lime mines.

In addition to the lime mine in the north, which is located on a small hill, there are many places in the north that are small hills, and among these dense hills, are there more resource mines? Is there coal and oil under the ground of the hill?

These are Li An's expectations, what resources are in front of the many small hills, these are what talents need to explore, Datang's exploration technology is also improving, after the technology is further matured, more and better resources can be explored.