Both Archie and Carleton, neither novices at the game, settled themselves snugly in their seats as the needle crept round the altimeter.  Cold awaited them in the higher levels.  That they knew.  A persistent, penetrating cold, driven by a keen wind right through some great-coats.  Leather is the best protection from that sort of wind.  The face feels it the most, however.  The cheeks become cold as ice.  Far below, the snakelike windings of trenches—–­trenches of friend and foe—–­can be followed from high altitudes.  Some parts of the line seem mile-deep systems of trenches, section on section, transverse here, approach line there, support line behind, ever joining one with another in wondrous fashion.  Shell-torn areas between the trench lines, the yellow earth showing its wounds plainly from well above, caught the eyes of the fliers.

The bark of a bursting anti-aircraft shell heralded their arrival in the danger zone.  From the earth the tiny white shell clouds have a fascination for the onlooker.  More so perhaps, than for the man in an aeroplane, not many yards distant from the bursting shrapnel.  The ball of fluff that follows the sharp “bang” is small at first, but unrolls itself lazily until it assumes quite a size.  That morning the anti-aircraft gunners seemed unusually accurate.  The third shell burst not far below the plane, and two bits of the projectile punctured the canvas with an odd “zipp.”  Some shells came so close that the explosions gave the machine a distinct airshock, though no other shell struck the plane.

Archie swung his plane now this way now that to render the aim of the “Archies” below ineffective, smiling to himself, to think that the nickname given to the anti-aircraft guns was his own given name.

“We are providing amusement for a pretty big audience, below there,” thought Archie.  “I suppose that the closer they come to us with those shells the better sport it is for those who are watching us.”

He laughed quietly at the thought.  He was as cool as possible that day.  In fact, he was unusually cool, for oftentimes the salvo of bursting “Archies” all about him would make his nerves tighten a bit.  That morning he was at his best.  He felt a calm confidence in his machine that made flying her a real pleasure.  It even added spice to the flight to know they had to pass so dangerous a locality before reaching the area which was their objective.  Over that area his observer was to hover sufficiently long to be able, on returning, to concoct a reliable and intelligible summary of what had come within his line of vision.

Carleton was soon busy with his glasses.  A group of cars on a siding near a station were carefully counted.  A line of horse transport on a country road was given considerable attention.  Working parties along a small waterway were spotted and located on the map.  A score of motor lorries, advertised by a floating dust cloud, scurried along below, to duly come under Carleton’s eye and be at once tabulated by him for future reference.  At one railway station a sufficient amount of bustle caused Carleton to watch that locality carefully.