2 . Silk was discovered by the Chinese more than 3,000 years ago. It was said that the wife of the Yellow Emperor accidentally dropped a silkworm cocoon(蚕茧) into her tea. The hot water caused the cocoon to break.     1     From then on, the silk industry began. At first, only the rich were allowed to wear silk clothes.

As early as 300 AD, Chinese businessmen sold silk to the Indians. By 200 BC, the Koreans had learned how to make silk. A 12,000-kilometer road going from China to Europe was built because of silk.     2    

Here's a simple version of how this amazing little thing does its work. The silkworm begins life as a moth(蛾子). The moth's life is about ten days, during which it lays eggs that change into silkworms.     3     In their short lives, 20,000 silkworms will eat more than one ton of mulberry(桑树) leaves, their main food.

    4     The finished cocoon contains 350 meters of silk. That might seem like a lot, but consider this: 5,500 silkworms have to spin 5,500 cocoons to make one kilogram of silk. People raise silkworms for silk production. The Chinese have perfected the art of making silk, gaining knowledge over many centuries.

Today, silk production remains an important economic risk in China.     5     Silk no longer costs an arm and a leg, but it is still highly prized.