Sherry Walker, age 12, of Lancaster, Pa., for her question:

Is it true that the United States has active volcanoes?

When the United States spread to include its present Pacific shoreline, it gained one active volcano and a few dying smoulderers. The one that was and still is rated as an active volcano is Mount Lassen in California. On May 30, 1914, after a long period of quiet, Lassen Peak erupted forth showers of sand, stones, dust and mud. Several mild outbursts came later, the last in February, 1921.

There are countless extinct volcanoes among the western mountains. Mt. Hood, Mt. Rainier, Mt St Helens and several others still send up a few plumes of gassy smoke from time to time. Alaska brought us active volcanoes in the far north. The Hawaiian Islands added to the United States some of the worlds most restless active volcanoes.