Nature has a number of different ways of burying and thus preserving the past. One way is by volcanic eruption. The most famous example is probably the great Roman town of Pompeii in southern Italy. The town was so quickly and completely covered with volcanic ashes from Mount Vesuvius one August day in 79 A.D. that the people of the town hardly knew what was happening to them. A second way may be seen in another part of Europe, where the surface of the land in the valleys of the Alps sank hundreds of years ago and was covered with water and peat. This cover preserved the wooden houses, utensils, and weapons of the prehistoric Alpine lake dwellers. In Egypt, drifting dry sands have preserved fragile records for thousands of years. In Central America, the jungle buried and preserved some of the ancient cities of prehistoric Indian peoples.

Q. Underline the sentence which shows that even delicate objects can be protected by nature for many years.