Dorn Beigh, age 10, of Harvard, I11., for his question:

Why is lightning crooked?

Our eyes are very quick to catch a picture and send it to the brain, and the brain can send back a quick answer in less than a second. But we need a longer look to study the fine details of an event. Our eyes may miss the actual details in a swift flash of lightning.

Most people think that lightning travels a jagged path with sharp turns and angled corners. The vivid flash is over in a fraction of a second and our eyes have no time to study its every move. But the camera can photograph it and the pictures give us time to look longer. They show that the fiery path does indeed jig jag from side to side. But the bends, as a rule, are wavy lines with rounded corners.

A thunderstorm is an immense electrical powerhouse reaching perhaps seven miles up into the atmosphere. Turbulent weather conditions in the moist cloud may build up more power than an early atomic bomb. The gathering storm brews huge charges of negative electricity in the 1ower cloud and huge positive charges in the upper levels.

These opposite charges strain to meet, neutralize each other and restore the electrical balance, They also attract the strong positive charge of the Earth's surface. But for a time, these charges are prevented from discharging themselves. Some substances help and others resist the passage of electric currents and discharges. Those that hinder electricity are called insulators, and a storm cloud is a tough insulator.