On days when the clouds form almost a solid flooring, one feels very much at sea, and wonders if one is in the navy instead of aviation. The diminutive Nieuports skirt the white expanse like torpedo boats in an arctic sea, and sometimes, far across the cloud-waves, one sights an enemy escadrille, moving as a fleet.

Principally our work consists of keeping German airmen away from our lines, and in attacking them when opportunity offers. We traverse the brown band and enter enemy territory to the accompaniment of an antiaircraft cannonade. Most of the shots are wild, however, and we pay little attention to them. When the shrapnel comes uncomfortably close, one shifts position slightly to evade the range. One glances up to see if there is another machine higher than one's own. Low and far within the German lines are several enemy planes, a dull white in appearance, resembling sand flies against the mottled earth. High above them one glimpses the mosquito-like forms of two Fokkers. Away off to one side white shrapnel puffs are vaguely visible, perhaps directed against a German crossing the lines. We approach the enemy machines ahead, only to find them slanting at a rapid rate into their own country. High above them lurks a protection plane. The man doing the "ceiling work," as it is called, will look after him for us.

TACTICS OF AN AIR BATTLE

Getting started is the hardest part of an attack. Once you have begun diving you're all right. The pilot just ahead turns tail up like a trout dropping back to water, and swoops down in irregular curves and circles. You follow at an angle so steep your feet seem to be holding you back in your seat. Now the black Maltese crosses on the German's wings stand out clearly. You think of him as some sort of big bug. Then you hear the rapid tut-tut-tut of his machine gun. The man that dived ahead of you becomes mixed up with the topmost German. He is so close it looks as if he had hit the enemy machine. You hear the staccato barking of his mitrailleuse and see him pass from under the German's tail.

The rattle of the gun that is aimed at you leaves you undisturbed. Only when the bullets pierce the wings a few feet off do you become uncomfortable. You see the gunner crouched down behind his weapon, but you aim at where the pilot ought to be--there are two men aboard the German craft--and press on the release hard. Your mitrailleuse hammers out a stream of bullets as you pass over and dive, nose down, to get out of range. Then, hopefully, you re-dress and look back at the foe. He ought to be dropping earthward at several miles a minute. As a matter of fact, however, he is sailing serenely on. They have an annoying habit of doing that, these Boches.

Rockwell, who attacked so often that he has lost all count, and who shoves his machine gun fairly in the faces of the Germans, used to swear their planes were armoured. Lieutenant de Laage, whose list of combats is equally extensive, has brought down only one. Hall, with three machines to his credit, has had more luck. Lufbery, who evidently has evolved a secret formula, has dropped four, according to official statistics, since his arrival on the Verdun front. Four "palms"--the record for the escadrille, glitter upon the ribbon of the Croix de Guerre accompanying his Médaille Militaire. [Footnote: This book was written in the fall of 1915. Since that time many additional machines have been credited to the American flyers.]

A pilot seldom has the satisfaction of beholding the result of his bull's-eye bullet. Rarely--so difficult it is to follow the turnings and twistings of the dropping plane--does he see his fallen foe strike the ground. Lufbery's last direct hit was an exception, for he followed all that took place from a balcony seat. I myself was in the "nigger-heaven," so I know. We had set out on a sortie together just before noon, one August day, and for the first time on such an occasion had lost each other over the lines. Seeing no Germans, I passed my time hovering over the French observation machines. Lufbery found one, however, and promptly brought it down. Just then I chanced to make a southward turn, and caught sight of an airplane falling out of the sky into the German lines.

As it turned over, it showed its white belly for an instant, then seemed to straighten out, and planed downward in big zigzags. The pilot must have gripped his controls even in death, for his craft did not tumble as most do. It passed between my line of vision and a wood, into which it disappeared. Just as I was going down to find out where it landed, I saw it again skimming across a field, and heading straight for the brown band beneath me. It was outlined against the shell-racked earth like a tiny insect, until just northwest of Fort Douaumont it crashed down upon the battlefield. A sheet of flame and smoke shot up from the tangled wreckage. For a moment or two I watched it burn; then I went back to the observation machines.

I thought Lufbery would show up and point to where the German had fallen. He failed to appear, and I began to be afraid it was he whom I had seen come down, instead of an enemy. I spent a worried hour before my return homeward. After getting back I learned that Lufbery was quite safe, having hurried in after the fight to report the destruction of his adversary before somebody else claimed him, which is only too frequently the case. Observation posts, however, confirmed Lufbery's story, and he was of course very much delighted. Nevertheless, at luncheon, I heard him murmuring, half to himself: "Those poor fellows."

The German machine gun operator, having probably escaped death in the air, must have had a hideous descent. Lufbery told us he had seen the whole thing, spiralling down after the German. He said he thought the German pilot must be a novice, judging from his manoeuvres. It occurred to me that he might have been making his first flight over the lines, doubtless full of enthusiasm about his career. Perhaps, dreaming of the Iron Cross and his Gretchen, he took a chance--and then swift death and a grave in the shell-strewn soil of Douaumont.