g at a lesser altitude.

The trenches, as he crossed the line, were only faintly discernible, the
detail obscured by the blue ground haze so common to the eyes of the
pilot operating at high altitudes. But the strip of barren land on each
side of the trenches gave visible evidence of the grimness of the
struggle far below, and here and there along the line, miniature geysers
spouted fan-shaped eruptions of earth with a grotesque, unexpected
suddenness. Then a second later a new pock-mark on the face of an
already over-tortured earth showed where the shell had exploded.

It was fascinating to watch. Nerve-racking and ear-splitting as it must
be to the mud-splashed creatures in the trenches below, from on high the
land within the neighborhood of the zig-zag trenches took on the
appearance of a pot of boiling mush--here a crater, there a crater,
springing into being with an amazing suddenness that lured the observer
into the game of guessing when the next crater would appear.

McGee was engaged in exactly such mental speculation when he was brought
to the realization of his own nearness to war by the plane-rocking
explosion of a well-placed Archie. Then two other giant black roses
bloomed directly in his path. Now he was presented with his own guessing
game. Where would the next one be?

He swerved sharply left and dived toward a neighboring cloud. A cloud,
while seeming from below to have both form and substance, is in reality
but little different from a dense ground fog. It is enveloping, misty,
eerie, and cuts off all visible contact with the world. If it covers a
large air area, then the pilot may face some nice problems in correct
and stable navigation, but if it is only a patch, he drives straight
along his course, knowing that he will plunge out into the sunlight with
the same suddenness with which he left it. Clouds are particularly
welcome when Archie gunners begin to plaster the air with high explosive
shells.

As McGee came out of this cloud, his attention was drawn to a number of
black bursts some three thousand feet below, but which clustered around
a lone Nieuport flying at a forty-five degree angle to the line of
flight which McGee was pursuing. That Archie crew knew their business,
and McGee thought they appeared uncomfortably near the Nieuport. Then,
as he watched, the Nieuport did a strange thing. Instead of making a
sudden change in direction or a quick dive, either of which would compel
the gunner