Somehow it interested Jack deeply to see those few meager lights where at other times the sky might have blazed with the electric glow, for Belgrade was always a little Paris of the Balkans. It seemed to speak of the terrible results that must follow in the train of a brutal war, civilization giving way to barbarity.
And there off to the right must be the Save River, flowing from far up in the region between the Croatian and the Bosnian provinces of Austria.
Back of this stream he knew there were heavy fortifications dominating the distant Serbian capital. It would seem that Austria had taken particular pains to threaten her fiery little neighbor on the south, possibly in hopes of some day stirring up another hornets’ nest in the Balkans, through which she might attain her selfish ends and annex new territory.
As their course did not lie in that direction Jack bothered himself not at all in connection with the Save batteries. He was, however, deeply interested in the ones he knew were located upon the lower heights. What peril they must face would spring from this source.
It was perhaps only natural that just then Jack should suddenly remember what had been said about searchlights. He wondered whether any were in use in this section of the fighting zone. Germans, French and British would certainly have carried such necessary appliances with them, but it was uncertain whether the Serbs or the Austrians had seen fit to install them here.
Now they seemed to be sweeping around the bend in the river. Jack could feel a new motion to the boat, which he believed must come from the addition of the Save waters to those of the Danube.
He watched both shores alternately. It was almost impossible to make out anything except where some height was dimly outlined against the clouded sky line. Then he turned his eyes aloft. The moon had risen, for in the east it was light compared to the west, though nothing of her silvery disc could be discovered.
Would the clouds continue to befriend the fugitives of the Danube through the dangerous passage of the batteries? If there came a break above even for a brief interval it might spell ruin for their hopes. And so Jack hoped most fervently that the clouds would prove merciful and keep on shutting off that light which, coming at an unfortunate moment, might mean their betrayal.
Without the slightest warning there came a sudden fearful sound. At the same instant they saw a vivid flash far back on the Austrian heights. Seconds followed, marked by the accelerated pulsations of their hearts. Then followed a crash and a flash over the place where the boys knew the capital lay in darkness and gloom.