may be other Huns about which you have not seen. You will probably think that a machine can be seen for a good many miles just because he is up in the air and you can look straight at him, but you never made a bigger mistake in your life. it depends on the clarity of the atmosphere, the position of the sun and machine with regard to yourself and whether the machine is above or below you, and how much so. Clouds, of course, are the great hiding places. Here the scout hides and watches a chance to pounce on the unwary aviator who approaches without the caution due the occasion. That kind of warfare is much like the old game of the footpads

BC Archives, 93-6553 Box 4 / DREWRY FAMILY / Selected Correspondence, 1917–1919.