Published as a pilot-training manual, it teaches proper aeronautical navigation techniques through the use of elaborate illustrations -- the kind of stuff that today might be called "info-graphics." "Flight thru Instruments" is so beautiful because it was created by the General Motors "Graphic Engineering" Staff under the leadership of Harley Earl.
Harley Earl worked as a designer at General Motors from 1929 until 1959, where he rose to become the postwar chief of GM's styling section. He drew styling inspiration from airplanes throughout his career, and Earl's most famous design innovation was a little trick he cribbed from the swooping rear fins of the P-38 Lighting fighter flown during World War II. Earl adapted the design for the 1948 Cadillac, and in a stroke, he set in motion a "tailfin" craze that would continue for more than a decade. Before that, however, he put his staff in the service of the war effort, and "Flight thru Instruments" was created in response to a US government contract.
Telstar Logistics http://telstarlogistics.typepad.com/telstarlogistics/air/page/9/
LINKS: Flight thru Instruments (additional illustrations from the book in a Flickr photoset)
Recalling the Graphics Feast At GM Styling During the War Years (Article about "Flight thru Instruments" on the "Official Harley Earl website.")

Foreword: Modern military missions, with their demand for precision flying at all times and under all conditions, cannot wait for daylight - or CAVU (ceiling and visibility unlimited). The pilot who cannot fly through instruments, therefore, consigns himself and his plane to a part-time job and places both in the premodern era where usefulness was limited by the amount of daylight and visibility. A pilot's usefulness in this age is almost proportional to his ability to fly through instruments. With the advent of the first flight-indicating instrument, flying cased to be strictly by contact. With the addition of each new flight-indicating instrument, flying by visual reference to the ground or the horizon became less important and less used, until today, it's instrument flying or else! And that is what it will be tomorrow. With the array of accurate and reliable instruments that are now standard equipment in all modern planes, flight is effective, precise, and successful under all conditions. These servants of flight attitude and performance are yours to command and to use if you will, but you must understand what they tell you and learn how to use them. This manual reflects the state-of-knowledge, the state-of-practice, and the state-of-the-art during the final phases of the Second World War. It addresses bombing missions, evasive action, and carrier take-offs and other operations. ( )