“Locate the machine gun battery if you can,” was the parting request to Tom and Jack as they prepared to ascend. “Send back word of the location as nearly as you can to our batteries, and the men there will see to the rest.”
“We will!” cried the Americans.
Locating a machine gun nest is not as easy as picking out a hostile battery of heavier guns, for the former, being smaller, are more easily concealed.
But Tom and Jack would, of course, do their best to help out their friends, the French. Over toward the German lines they flew, and began to scan with eager eyes the ground below them. They could not fly at a very great height, as they needed to be low down in order to see, and in this position they were a mark for the anti-aircraft guns of the Huns.
They had no sooner got over the enemy trenches, and were peering about for the possible location of the machine gun emplacement, when they were greeted with bursts of fire. But by skillfully dodging they escaped being hit themselves, though their machines were struck. The two chums were separated by about a mile, for they wanted to cover as much ground as possible.
At last, to his great delight, Tom saw a burst of smoke from a building that had been so demolished by shell fire that it seemed nothing could now inhabit it. But the truth was soon apparent. The machine gun nest was in the cellar, and from there, well hidden, had been doing terrible execution on the allied forces. Pausing only to make sure of his surmise, Tom began to tap out on his wireless key the location of the hidden machine gun nest.
Most of the aeroplanes carry a wireless outfit. An aerial trails after them, and the electric impulses, dripping off this, so to speak, reach the battery headquarters. Owing to the noise caused by the motor of the airship, no message can be sent to the airman in return, and he has to depend on signs made on the ground, arrows or circles in white by day and lighted signals at night, to make sure that his messages are being received and understood.
The Allies, of course, possess maps of every sector of the enemy's front, so that by reference to these maps the aircraft observer can send back word as to almost the precise location of the battery which it is desired to destroy.
Quickly tapping out word where the battery was located, Tom awaited developments, circling around the spot in his machine. He was fired at from guns on the ground below, but, to his delight, no hostile planes rose to give him combat. A glance across the expanse, however, showed that Jack was engaging two.
“He's keeping them from me!” thought Tom, and his heart was heavy, for he realized that Jack might be killed. However, it was the fortune of war. As long as the Hun planes were fighting Jack they would not molest him, and he might have time to send word to the French battery that would result in the destruction of the Hun machine nest.