From Leaf to Thread: Reread and Check

From Leaf to Thread: The Story of Silk

1Silk is one of the smoothest, shiniest cloths in the world, and it is also very strong. The surprising part is where it comes from. Silk is made by silkworms. In spite of their name, silkworms are not really worms at all. They are the caterpillars of an insect called the silk moth.

2A silk moth lays hundreds of tiny eggs. When the eggs hatch, the caterpillars are smaller than a grain of rice. They begin to eat right away, and they eat almost nothing but mulberry leaves. For several weeks, they munch day and night. As they grow, they shed their skin a few times, and each time they come out bigger.

3When a silkworm is fully grown, it stops eating and begins to spin a cocoon around itself. The silkworm makes silk inside its body and pushes it out through tiny openings near its mouth. It swings its head back and forth, again and again, wrapping itself in the thread. After a few days, the cocoon is finished. Each cocoon is made of a single thread that can be longer than a football field.

4To make silk cloth, workers first soak the cocoons in hot water. The hot water softens the sticky gum that holds the thread together. Then workers carefully unwind the thread from each cocoon. The thread is wound onto a wheel called a reel. One thread is too thin to use by itself, so several threads are twisted together. These stronger threads are used to weave cloth.

5People in China were the first to make silk, thousands of years ago. For a long time, they kept the way silk was made a secret. Traders carried silk to faraway lands along long trade routes. Along the way, they traded silk for other goods, such as horses, glass, and spices. Many traders traveled in caravans. These long lines of people and camels moved slowly across hot deserts and over high mountains. Later, these routes became known as the Silk Road.

6Today, silk is made in many countries. People use it for scarves, ties, dresses, and sewing thread. The next time you touch something made of silk, think about the tiny caterpillar that spun it, one long thread at a time.