Curt Walker, age 12, ofVisalia, Calif., for his question:

How was petroleum first found?

Here and there oil deposits near the surface seep out into the air. As a rule, they become pools of pitch or asphalt. The ancient Egyptians used pitch to mummify their dead, and a pitch burning candle was set in the floating cradle of the baby Moses. Asphalt was used around 600 D.C. to pave the streets of old Babylon.

In the New World, the Indians used surface petroleum deposits to glue tiles together, as fuel oil and also as medicine. Kit Carson once sold petroleum as a medicine. It has been used in many ways by many people since ancient days, but the modern petroleum industry began soon after 1852, when the tacky stuff was found to yield burnable kerosene.