"Let her go!" exclaimed Harris to Jack, and the latter nodded to the
mechanician, who, after the order of "contact," spun the blades
again and they were really off, together with the others.

Up and up went Jack, sending his machine aloft in big circles as the
others were doing. Before him on a support was clamped a map,
similar to the one supported in front of Harris, and by consulting
this Jack knew, from the instructions he had received before going
up, just what part of the enemy's territory he was to cover. He was
under the direction of the photographer and map-maker, for the two
duties were combined in this instance.

Up and up they went. There was no talking, for though this is
possible in an aeroplane when the engine is shut off, such was not
now the case. But Jack knew his business.

His indicator soon showed them to be up about fourteen thousand
feet, and below them an artillery duel was in progress. It was a
wonderful, but terrible sight. Immediately under them, and rather
too near for comfort, shrapnel was bursting all around. The
"Archies," or anti-aircraft guns of the Germans, were trying to
reach the French planes, and, in addition to the bullets, "woolly
bears" and "flaming onions" were sent up toward them. These are two
types of bursting shells, the first so named because when it
explodes it does so with a cloud of black smoke and a flaming
center. I have never been able to learn how the "onions" got their
name, unless it is from the stench let loose by the exploding gases.

Though they were fired at viciously, neither Jack nor his companion