Meanwhile every big gun belonging to the French had been battering the trenches of the Germans until they had the occupants cowering as far down in the earth as they could get.
Nor were the German guns idle all this while. Far-away they lay in their coverts, hidden from the view of passing aviators by a generous use of tree branches and painted canvas. Monster shells were passing through the air at all times, and at great altitudes, since they were meant to fall miles and miles distant.
We-ee!
“Great Scott! What’s that?” yelled Tom, but without being heard.
It was one of the great shells whistling past the plane in which Tom and the grizzled sergeant were seated. It came so close to them that the machine rocked violently. Tom felt cold at the thought of what would have happened had it by some mischance actually struck their plane.
“Some escape!” murmured the young aviator.
Here and there far down below him he saw spurts of flame bursting out from behind what he knew to be woods. Here there must be batteries in hiding, now taking part in deluging the German front with a hurricane of iron.
Meanwhile that wave of Frenchmen, their overcoats with the fronts fastened back so as to leave their knees clear, kept on advancing steadily. They would arrive at the enemy trenches presently, when those in hiding would make their presence felt with innumerable quick-firing guns and trench bombs in the endeavor to eject the invaders.
There they would either die, or else surrender, because flight had been made utterly impossible. The barrage had been lifted, and covered a line just beyond the German first trenches. To pass through this hail of fire and live was out of the question, so that the German defenders were in a trap.
All this while Tom had been kept fairly busy. His pilot managed the plane adroitly so as to afford the observer an excellent chance to receive and send signals. Tom kept his glass fixed on the plane far ahead, from which his messages came. He did not know all they stood for; that was not his business. His duty was to send them on exactly as they were received.