The hatred in the hearts of the Huns, expressed by the constant "whonk" of bursting anti-aircraft shells, contrasts disagreeably with the loveliness of the moonlit panorama. All man's disfigurements of the earth are obliterated by distance and nothing but a scene of inspiring beauty is in view from the aviaors' lofty outlook at a height of several thousand feet. The flashings of the guns, the "flaming onions,"--i.e., strings of phosphorus balls shot up to light the sky and to ignite any inflammable substance with which they come in contact,--and the black puffs of smoke from the bursting shells add a weird and startling brilliancy to the surroundings. No matter how many times a man may fly at night the immensity of the heavens above him, crowded with unknown worlds, cannot fail to impress him with his own insignificance in the general scheme of the universe, and Death itself appears of small importance compared to the way in which he faces it. The aviators, however, have little time for reflection, for on a long flight they must keep a constant outlook for such landmarks as will enable them from time to time to mark their exact position on the chart and by comparison with their compass course and "ground speed" vary their course according to changes in direction and velocity of wind. An instrument called the "pitot tube" indicates the speed at which the aeroplane passes through the air, but the speed at which the plane travels in relation to the ground depends on the direction and velocity of the wind. They must also watch the flashes from anti-aircraft batteries and pin-point them on their maps if possible; aerodromes which are lit up, train movements, the lighting of towns, the blaze of steel factories; in fact everything of military importance must be recorded and reported upon, if accurately located. The night aviator, however, must be extremely careful in his observations, for it is very easy to get lost and it is extremely difficult to keep an accurate check, on the charts, of your exact position over the ground, even after long practice; especially is this true when the flight covers three to four hundred miles in distance and lasts from eight to nine hours.