Four plaques engraved with the word "Source City" and painted with black dye hung above the four gates of Source City, and the first city of the Dragon Tribe finally had its own name.

Source City, the origin city of the dragon tribe, the city of beginning, the people of the dragon tribe know the meaning of the source city from the mouth of the king, this is only the first city of the dragon tribe, the dragon tribe will have more cities in the future, the second city will start to be built next year, the more cities the dragon tribe has, the stronger the dragon tribe is.

In fact, the source city is not a city, just a separate city, the city, the city represents the city wall, the pool represents the moat, and the city is just Su Yan's habitual name for a city.

The first city of the Dragon Tribe will be completed this year, and the appearance of the first city is of extraordinary significance to the Dragon Tribe, representing that the Dragon Tribe is moving from a tribe to a state, and even from a public ownership society to a private ownership society.

The first step is weights and measures, that is, length, weight, and volume, but Su Yan will also increase time, area, and volume.

In the dragon tribe, the length unit has been determined, and when the coarse bronze artifacts were first cast, Su Yan cast a copper ruler two feet long, and after determining the length unit, the utensils of the same size could be manufactured in batches according to the standard.

If you are not sure about the length unit, you can also make the same size artifact in batches, before the length unit appeared, the dragon tribe wanted to describe the length mainly with the length of a wooden stick for comparison, this method is obviously more troublesome.

In fact, at present, the dragon tribe does not appear standard weights and measures will not affect the development of the dragon tribe, but the appearance of weights and measures has a certain role in promoting the development of the dragon tribe, at least in many cases can save a lot of time, and there is no need to follow the feeling when grabbing the medicine, and the various components of the medicine can be accurately determined.

The unit of length has been determined, from long to short are li, zhang, ruler, inch, minute, centimeter, milli, except for one mile is equal to two hundred zhang, the rest are decimal system, one foot contract modern thirty centimeters, one mile contract six hundred meters.

When the length unit is determined, the area unit and the volume unit are determined, that is, the square or cube is added to the length unit.

Among them, it should be noted that the area unit of "mu", one mu is equal to one mile multiplied by one-third zhang, so one mu is about 600 square meters.

Length, area, volume units and modern units are different, this is also a matter of no way, Su Yan can not accurately measure a length, can only measure an approximate length, in this era, Su Yan made the standard, will follow this standard in the future.

Su Yan's system of weights and measures is mainly ancient Chinese weights and measures plus a small number of modern weights and measures, which are mixed together.

Next is the unit of weight, from heavy to light are tons, stones, catties, two, money, cents, one ton is equal to two thousand catties, one stone is equal to one hundred catties, the rest are decimal system, one catty is about equal to five hundred grams in modern times, one cent is about one half of a gram.

Milliliters, liters, buckets, and dunkiens are volume units, and 1,000 milliliters are one liter, and 10 liters are buckets, and 10 buckets are hu.

Length, area, volume, weight, volume, these units of weights and measures Su Yan can be compared, and set a standard, copper ruler to determine the length, copper ingot to determine the weight, pottery to determine the volume, only the time unit is the most troublesome.

The unit of time is divided into large units and small units, with large units determining one year and small units determining one day.

The small unit has 12 hours a day, 4 quarters of an hour at 10 hours, 30 minutes at a quarter of an hour, and 60 minutes a minute.

The sundial (gui), one of the oldest timekeepers in China, is a device that uses the shadow cast by the sun to determine the time, roughly accurate to the quarter hour, and this invention has been used for thousands of years, until the advent of mechanical clocks replaced the sundial.

A sundial usually consists of a bronze hand and a stone disc that depicts the time around the disc and the time when the shadow of the hand is cast.

The sundial is not difficult to make, the time division of the day can be roughly determined through the sundial, and the most difficult thing is to determine the large unit of time.

The large units are year, month, and day, of which the season can be added between the year and the month, and the month and day can be added, and the year is divided into four seasons, and January is divided into thirty years.

Every day, Su Yan would carve a trace on the stone slab or animal skin to represent the time of the day, so Su Yan could conclude that the year was about 360 days, and the exact time of the year could not be determined.

For the lunar calendar, Su Yan is very familiar, but Su Yan has no way to use the lunar calendar for the time being, the lunar calendar is very complicated, take the change cycle of the moon phase, that is, the synodic month as the length of the month, refer to the solar return year as the length of the year, and set the 24 solar terms and leap months to adapt the average calendar year to the return year.

In the future, a large amount of manpower can be gathered to formulate a lunar calendar suitable for the use of the dragon tribe, but not now, now Su Yan can only simply and vaguely divide the year.

The year is divided into four seasons, and there is no way to determine the exact division of the seasons, Su Yan often uses the first scene of late spring to represent the arrival of summer, the large amount of ripe fruits at the end of summer to represent the arrival of autumn, the first snow of late autumn to represent the arrival of winter, and the melting of ice and snow at the end of winter to represent the arrival of spring.

Each season is divided into three months, the first two months are thirty days, but the last month is of variable length.

The general division is like this, the length unit has been determined before, and now Su Yan has led people to use copper ingots to determine the weight, pottery to determine the volume, and sundials to indicate the time, and these three units have also been determined, and Su Yan has to come in person to make these three things, he is the one who determines the standard, and no one else can help him with this work.

In just two days, Su Yan led his people to make various copper ingots representing the weight units below the "jin" and pottery representing buckets and shengs, leaving only sundials.

To the sundial here, it takes a lot of time, the time spent is not on the production of the sundial, the sundial has two components, a copper needle, a disc, the production is very simple, the time mainly spends the sundial under the sun, only according to the rules of finding the place, the sundial can be used as a timer.

It was an experiment that went back and forth to find the angle of the sundial, and it took several days to finally find a similar angle.

The first sundial of the dragon tribe was placed in the open space in front of the temple, and Su Yan specially arranged for a few minors to watch the time display on the sundial every day, and every hour, they would pick up the gong and strike it while walking, informing all the clansmen of the current time.