An episode of The Engines of Our Ingenuity, numbered 3394, is available from Houston Public Media. This episode discusses an old book related to World War I aeroplanes. The book is said to reveal information about technological change during wartime.

It apparently conveys an unintended message, although the specifics of this message are not provided here. For more information about episode 3394 and its discussion of the old book, readers in Tomball, TX, can consult the source directly at Houston Public Media.