The First Emperor-Ending
At the same time, Qin Shi Huang announced that the Qin State's round bronze coins with square holes, with a standard weight of 25 grams, should be used across the country, rendering invalid the currencies of the other six states. The emperor also ordered standardization of the units of weights and measurements. In order to facilitate the spread of government policies and laws, as well as to promote cultural exchange, he unified the Chinese script, designating "Xiaozhuan," or the seal script, as the standard script. Later, "Lishu," literally "official script," which was easier to write than "Xiaozhuan," was developed based on popular writing habits. Lishu was quite similar to "Kaishu," or the regular script, widely used today.
The series of measures that Qin Shi Huang took, such as abolishing of the fief system, and unifying the currency, units of weights and measurements and the script, were conducive to cementing unification and promoting social, economic and cultural development. These should all be deemed remarkable contributions made by the emperor. The wall had an intricate structure. The wall itself was made of rammed loess, which was very solid. Along its top was a parapet wall with holes through which soldiers could keep watch for the enemy in hiding. The Great Wall was dotted with strongholds, which served as watchtowers. In addition, signal towers were built at strategic points. When they saw any sign of approaching enemies, the soldiers would light fires to signal each other so that all the frontier troops could be informed of the situation and prepare to fight the invaders.
Over a long period of time, the Great Wall served as a defense work against the hostile nomads to the north, helping to safeguard the agricultural economy in China's Central Plains. A number of later dynasties also constructed walls for the same purpose, the most famous of which was the Great Wall of the Ming Dynasty. Today, the Great Wall is more often regarded as a magnificent cultural heritage that the ancient Chinese left to the world.