For example, the crack widening in the window of the plane flying over Greenland: crazing is the word used by the safety inspector to describe the mesh of lines spreading from the bullet-sized hole in the plastic through which shine glaciers melting in the sea below—ridge upon white ridge gleaming in the sunlight of an autumn morning, which goes on and on as the plane heads westward. The inspector contracts and releases the muscles in his legs, curling his toes under the seat in front of him, raising and lowering his feet, listening, again, to a partita by Bach. Soon it will be time for another meal, another film, and the blue expanse of the sea. The flight seems endless, suspended like a breath above the earth, a line inscribed in the sky subject to the same forces of gravity and velocity that mark the rising tides. The passenger closes his eyes, and as he falls asleep he thinks, I must be crazy to keep doing this. The crack opens into light.