Katherine MacLean

“ The sun poured down its flood of light, here and there energizing a molecule of the blue air into little sparkles of ionization; and below, a mist of bright clouds half veiled the darkness that was the bottom.
"What's it mean when someone blinks blue light in lots of flashes, and then glows red and starts sinking, huh, Grandpa?" ”

“ It flashed by, and the youngster thought they were going to lose it—it was going so much faster than they; but as the thought crossed his mind, and he saw the two churning glowing openings in its rear, a burning blast of energy struck him. A multitude of glowing, charged particles crackled around him, streamed against him. His fields shifted to reach out and capture them; the spin of stored energy within spun faster, absorbing the new energy into its drive, its life-pulse rising to a deep hum, and he felt strong, stronger than he had ever felt before in his life. ”

“ Can you really get too much?” The youngster jigged up and down a little with excitement and anticipation.
For a moment, the oldster turned his attention from watching for the thing that was coming, and considered him fondly. “Poor youngling. I forget. You've had no chance to learn what it means to get enough. You're too young to ride the storms and tap the lightnings... Listen now. When a grownup has to let out a flash of blue light, that means that he's overcharged and spinning off balance inside, and so he has to save himself by letting out his energy to let down the pressure. ”