I sit up. A shiver, and a return beneath the blankets for five minutes' rumination. Dressing will be dashed unpleasant in the cold of dawn. The canvas is wet with the night's rain. The reconnaissance is a long one, and will take fully three hours. The air at 10,000 feet will bite hard. Must send a field post-card before we start. Not too much time, so out and on with your clothes. Life is wrotten. While dressing we analyse the weather, that pivot of our day-to-day existence. On the weather depends our work and leisure, our comparative risks and comparative safety. Last thing at night, first thing in the morning, and throughout the day we search the sky for a sign. And I cannot deny that on occasions a sea of low clouds, making impossible the next job, is a pleasant sight. The pale rose of sunrise is smudging over the last flickerings of the grey night. Only a few wisps of cloud are about, and they are too high to bother us. The wind is slight and from the east, for which many thanks, as it will make easier the return half of the circuit. We wrap ourselves in flying kit and cross the road to the aerodrome. There the band of leather-coated officers shiver while discussing their respective places in the formation. A bus lands and taxies to a shed. From it descends the Squadron Commander, who, with gum-boots and a warm coat over his pyjamas, has been "trying the air." "Get into your machines," he calls. As we obey he enters his hut-office and phones the wing headquarters. The major reappears, and the command "Start up!" is passed along the line of machines. Ten minutes later we head for the trenches, climbing as we travel. It was cold on the ground. It was bitter at 5000 feet. It is damnable at 10,000 feet. I lean over the side to look at Arras, but draw back quickly as the frozen hand of the atmosphere slaps my face. My gloved hands grow numb, then ache profoundly when the warm blood brings back their power to feel. I test my gun, and the trigger-pressure is painful. Life is worse than rotten, it is beastly. But the cold soon does its worst, and a healthy circulation expels the numbness from my fingers. Besides, once we are beyond the lines, the work on hand allows small opportunity to waste time on physical sensations. On this trip there is little interruption, thank goodness. Archie falls short of his average shooting, and we are able to outpace a group of some twelve Hun two-seaters that try to intercept us. The movement below is noted, the round is completed according to programme, and we turn westward and homeward. Have you ever sucked bull's-eyes, respected sir or madame? If not, take it from me that the best time to try them is towards the end of a three-hour flight over enemy country. Five bull's-eyes are then far more enjoyable than a five-course meal at the Grand Babylon Hotel. One of these striped vulgarities both soothes and warms me as we re-cross the trenches.