When I leave a cloud, drowsiness advances; when I enter the next, it recedes. If I could sleep and wake refreshed, how extraordinary this world of mist would be. But now I only dimly appreciate, only partially realize. The love of flying, the beauty of sunrise, the 
solitude of the mid-Atlantic sky, are screened from my senses by opaque veils of sleep. All my remaining energy, all the attention I can bring to bear, must be concentrated on the task of simply passing through.
Lindbergh, C. (1953) . The Spirit of St. Louis. New York: Scribner's Sons. (Link)