CHAPTER XVIII
A CLOUD BATTLE
For some little time the picked squadron that was intrusted with the difficult and dangerous task of locating the big German gun flew over the French lines. Below them Tom and Jack could make out various French camps, the front and supporting lines of trenches, and various other military works. They could see a brisk artillery duel going on at one point. They noted the puffs of smoke, but of course could not hear the explosions, as their own motors were making too much noise.
Tom and Jack kept within sight of one another, and also within view of their comrades. Each plane was marked with a big number so it could be distinguished, for the aviators themselves were so wrapped in fleece-lined clothes, so attired in gauntlets, goggles and fur boots, as protection against the terrible cold of the upper regions, that one's closest friend would not recognize him at a near view.
It was the object of this first scouting expedition to make a preliminary observation over as wide a range of the enemy's country as possible.
