Delonia Watson, are 11, of Shreveport, Louisiana, her question:

Why did 'the Egyptians use obelisks?

Archeologists suspect that the obelisk was a very sophisticated descendant of the shadow stick. If this is so, its ancestors date back to the dim past. When our wandering ancestors settled down in communities, they had more time to study the world around them. And one df the first things that interested them was the passim; of time. They noticed that the sun casts shadows that change through the day. They also noticed that these changes were related to the sun's daily path over the sky. It was a simple step to use these changing shadows as a timepiece.

All early communities seem to have    used shadow sticks long before the dawn of history. A simple pole was set into the ground and its shadow traced through the day. The long morning shadow pointed westward and gradually shrank as the sun rose higher in the sky. It was shortest at high noon and then swung eastward, growing longer until sunset. Through the ages, the useful shadow stick was made more ornate. It became a stone obelisk, adorned with carvings. Fay this time it was used as a direction marker,and its carvings were often reports of historical events.