William L. Fisher, age 10, of Louisville, Ky., for his question:

When were the Adirondacks formed?

The green shouldered Adirondacks are a range of the massive Appalachian Mountains, This vast system stretches some 1500 miles down the eastern seaboard and the old earth took many millions of years to make it all. The Appalachians, with their many folded ranges, were not made all at the same time.

The northern arm of the massive system arose some 300 million years ago. These ancient ranges include the beautiful Adirondacks of new York. The southern arms of the Appalachians began their growth about 200 million years ago, when the Adirondacks were already about 100 million years old.