“Watch him!” snapped Rob, and all eyes were again focussed on the far distant object moving across the heavens, and passing some fleecy fragment of a floating white cloud.
“As sure as anything he’s dropping on a regular toboggan slant!” cried Andy, thrilled by the sight.
“Huh!” remarked the wise Tubby, with the pride of superior knowledge, “that’s what they call volplaning. Sometimes an aviator will shoot down for a mile like a streak of lightning, and just when you think he must be smashed against the ground he’ll suddenly stop, just like a descending eagle does, and sail away as nice as you please on a lower level.”
“Which is exactly what that spy is doing right now!” exclaimed Andy. “I guess he is down far enough for him to see all he wants to, and also snap off some pictures. But, Rob, if there are Canadian troops guarding the bridge across there why wouldn’t they give him a volley to let him know he hadn’t any business on that side of the International Line?”
“I expect that’s what they will do any minute now,” Rob assured him. “We may not hear the sound of the guns over here; miles lie between; but we ought to be able to tell by the actions of the aviator. If the lead commences to sing about his ears, he’s likely to mount again; he’ll be afraid of having his gasolene tank pierced by one of them, or be struck himself.”
“When we were on the other side, Rob,” interjected Tubby, “you know we always said petrol instead of gasolene; but they both mean the same thing. There, look, will you; he’s started up again, as sure as anything, making spirals, as they generally do when ascending in a big hurry.”
As Tubby declared, the man in the aeroplane had suddenly changed his location and was now ascending as fast as he could. Something had undoubtedly caused him to do this. Rob said he wished he had thought to fetch a pair of binoculars along with him, for then they might see spurts of smoke on the ground, and possibly even discover the bridge itself.
“But then who would ever dream we’d want glasses for such a purpose?” Tubby observed. “Goodness knows we’re lugging enough load as it is. He is turning around now, Rob, and heading this way again. Do you think he accomplished his purpose, and is now bent on getting out of range of those bullets?”
“Very likely,” the other replied, “though his danger was more imaginary than real. To strike a moving aeroplane at that height with an ordinary military rifle would be next door to an accident. Haven’t we seen air pilots take all sorts of daring chances, with shrapnel bursting all around them?”
The three scouts watched until the mysterious machine had vanished toward the south. They could hear the sound of the motor as it passed high overhead, though at a considerably lower level than when going the other way.