Howard Jankowski, age 16, of Portland, Ore., for his question:

WHO WAS SIR HUMPHREY DAVY?

Sir Humphrey Davy is a famous English scientist who discovered the chemicals potassium and sodium. He also invented a miners safety lamp, called the Davy lamp, that greatly reduced the risks of coal mine explosions.

Perfected in 1815, the small, oil burning safety lamp was covered with a cylinder of wire gauze that absorbed the heat of the flame, thus greatly reducing the danger of fires and explosions in mines.

Davy was born in 1778. As a young man, he liked writing verses and also enjoyed hunting and fishing. He became a chemist and by the time he reached the age of 20 he was a laboratory superintendent of a medical institute. There he discovered the properties of nitrous oxide, or laughing gas, which is still used as an anesthetic in dentistry.

Davy became a lecturer and wrote a number of important books. He became famous because of his discoveries and was knighted in 1818.