Jack and Tom ran serious risks, for the Germans, realizing that the two leading planes had some special mission, attacked them fiercely. Tom managed to shake off and disable his antagonist. But Jack's man shot with such good aim that he pierced his gasolene tank, and had it not been that Jack was able to thrust into the hole one of some wooden plugs he had brought along for the purpose, he might have had to come down within the German lines. But the wood swelled, filled the hole, and then the petrol came out so slowly that there was comparatively little danger.
And having, with some of their companions, fought their way through the German air patrol, and having escaped with minor damage to their guns, Jack and Tom looked down at the place where they had seen the queer lights.
And then, high up and at a vantage point, while below them hovered their photographing planes, the two young aviators beheld a curious sight.
In German-occupied territory, but on French soil, they saw near a railroad junction, where they were fairly well hidden in a camouflaged position, not one, but three monster Hun cannons. The guns looked more like gigantic cranes than like the accepted form of a great rifled piece of armament. The guns were so mounted that they could be run out on a small track at the moment of firing, and then propelled back again, like some of the disappearing cannon at Sandy Hook and other United States forts. Only the German guns advanced and retreated horizontally, while the usual method is vertically.
"We've discovered 'em! There they are!" cried Tom, but of course he could not hear his own voice above the roar of his motor. But he knew that he and Jack were over the very spot where the night before they had seen the colored flares from the great guns.
And they had, indeed, by a most lucky chance, located the big German guns, for there were three of them. They were placed almost midway between the railroad station of Crepyen-Lannois and the two forts known as "Joy Hills," forts which had fallen into German hands. There were two railroad spur lines from the station, and on these the heavy guns were moved to position to fire, and then run back again. Other spur lines were under course of construction, Jack and Tom, as well as the other airmen, could observe, indicating that other guns were to be mounted, perhaps to take the place of some that might be destroyed.
As a matter of fact, as was learned later, there were but two guns in service at this time, one of the three having burst.[1]
Even as the French squadron came hovering over the place where the German monster guns were placed, the advance of Tom, Jack and their comrades being disputed by the Huns, one of the super-guns was run out to fire on its specially constructed platform.
That this should be done in the very faces of the French was probably accounted for by the fact that the Germans were taken by surprise. It took some little time to arrange for firing one of the big cannons, and it was probably too late, after the French airmen were hovering above it, to get word to the crew not to discharge it.
As it happened, Tom and Jack, with Boughton, who had kept pace with them, witnessed the firing of the big gun. As it was discharged, ten other heavy guns, but, of course, of much less range, were fired off, being discharged as one to cover the report of the giant mortar. And at the same time dense clouds of smoke were sent up from surrounding hills, in an endeavor to screen the big gun from aeroplane observation. But it was too late.