Jimmy O'Connor, age 8, of Williamsport, Pennsylvania, for his question:

Where is the oldest volcano?

Volcanoes erupt, now and then, and pile up great mountains of ashes and rocky lava. They may be active for a few thousand years or

for many millions of years. Finally they die down and only their mountains are left. Some of the oldest volcanic mountains erupted in Maine and New Brunswick 300 million years ago. About 200 million years ago, others erupted in India and, some time later, volcanoes erupted in New England. All these have been quiet for ages and only their old volcanic mountains are left.

About 50 million years ago several volcanoes erupted in the Mediterranean region. In Italy, Mount Vesuvius is still restless. So is Mount Etna on the island of Sicily. These are among the world's oldest active volcanoes on the dry land. However, there are many volcanoes under water, deep down on the floor of the sea. Nobody knows exactly how long they have been active, but some are much older than the land volcanoes.