In the final years of the Warring States period, Qin Shi Huang, with his extraordinary ambition, conquered the six kingdoms of Han, Wei, Chu, Zhao, Yan, and Qi, unifying the realm. He had all the gold, silver, and rare treasures amassed in their palaces transported to the Qin capital, Xianyang, and stored in the imperial treasury.
Among countless treasures, three exquisite pieces stood out as rare wonders of the world.
One of the items was a five-branched lamp carved from green jade, standing seven and a half feet tall, adorned with a hornless dragon that held the lamp in its mouth; when lit, the dragon's scales shimmered and moved. Around the lamp were twelve bronze figurines, each holding instruments like zithers, flutes, and reed pipes, inlaid with jewels and inscribed with the words "Music of Fanma."
The second item was a jade tube, two feet three inches long with twenty-six holes. It was said that as soon as it was played, rolling mountains and galloping chariots would appear before the eyes, with the sound of phoenix bells ringing incessantly. When the music stopped, the vision would vanish, and the bells would fall silent. On the back of the tube were engraved four characters: "Zhaohua's Flute."
Even more remarkable was a square mirror, four feet wide and five feet nine inches tall, crystal clear on both sides. When someone stepped directly before it, the mirror showed an inverted reflection. If they pressed a hand to their chest and looked again, it revealed their internal organs—intestines, stomach, heart, lungs, liver—without causing any harm; if they were ill, the mirror pinpointed the disease's location. It was said this mirror could also distinguish righteousness from evil: any woman harboring wicked thoughts would show her gallbladder swelling and heart racing. After Emperor Qin Shi Huang acquired this treasure, he often used it to inspect his palace maids. Whenever he spotted one with a swollen gallbladder and racing heart, he immediately ordered her execution. Countless innocent women met their deaths under his blade.
After the First Emperor of Qin died, his son Qin Er Shi took the throne. Soon, Chen Sheng and Wu Guang raised the standard of revolt at Daze Village, followed by Liu Bang and Xiang Yu. In 206 BCE, Liu Bang led the Han army into Xianyang, opened the Qin imperial treasury, and marveled at the rare treasures inside. But shortly after, Xiang Yu breached the pass, set the Qin palaces ablaze, and looted vast riches. From that day on, the legendary Qin Mirror and other priceless artifacts vanished without a trace.
Later, the idiom "Qin Mirror Hanging High" came to be used as a metaphor for being able to distinguish right from wrong and discern good from evil.
Source: *Miscellaneous Records of the Western Capital*
Meaning of the Idiom: Later, the Chinese idiom "秦镜高悬" came to describe how being able to distinguish right from wrong and discern good from evil.