Barbara Vitanyi, age 12, of Bridgeport, Con.

What lights the floor of the ocean?

Sunlight passes clear through the air until it is stopped by the solid ground. However, it cannot pass through water as easily as it passes through the air. It gets through the surface grater but as it goes deeper it slows up and finally fades. Sunlight gets through the water of a swimming pool and even through a pond or river. It lights the floor of the pool and even the floor of a clear lake or river. But all the light is spent long before the sunshine reaches the floor of the deep ocean. Down there is a dark and endless night.

Bright, clear sunlight pierces the sea for not more than 100 to 150 feet below the surface. Then certain of the colored rays begin to fade. The red rays begin to go first. At 200 to 300 feet, the reds and the warm golden rays have all faded. The green rays of the spectrum may pierce down 1000 feet. When they fade, only the brilliant blue and violet colors are left. Clear ocean water may keep a tinge of violet 2000 feet down. Below that no sunlight of any sort can reach and the deep ocean is a black abyss.