Ayn Rand, Atlas Shrugged
Far in the distance, beyond the mill structures, she saw a string of gondolas waiting on a siding. The bridge of an overhead crane cut the sky above them. The crane was moving. Its huge magnet held a load of rails glued to a disk by the sole power of contact. There was no trace of sun in the gray spread of clouds, yet the rails glistened, as if the metal caught light out of space. The metal was a greenish-blue. The great chain stopped over a car, descended, jerked in a brief spasm and left the rails in the car. The crane moved back in majestic indifference; it looked like the giant drawing of a geometrical theorem moving above the men and the earth.