Billy Will, age 14, of Richmond Va., for his question:

WHAT IS SCURVY?

Scurvy is a disease caused by lack of ascorbic acid in the diet. Ascorbic acid is vitamin C, and is found in citrus fruits, tomatoes, raw cabbage and lettuce, celery, onions, cress, fresh carrots and potatoes.

If a person doesn't get enough vitamin C, bruises develop easily and wounds heal poorly. The mouth and gums become sore as do joints. He might also develop anemia.

Improved understanding of food requirements have made scurvy extremely rare. Today you find it only occasionally in babies and elderly persons whose diets are inadequate.

Scurvy was once a common disease among sailors. Then James Lind, a Scottish doctor, discovered in 1795 that a daily ration of lemon juice would prevent illness.