"We are in a trap," said Alfred.
Gascon smiled. "Yes, if they have advanced beyond the battery we shall have to wait until night, because it would be unsafe to cross the Meuse in their rear."
A boom from the east, followed by another, and still another, was sufficient notice to them that the great forts at Liège were answering the challenge. They burrowed into the hedge, and made enclosures with bushes and leaves. Meantime, the battery on the hill opened fire with its three guns, and soon the surrounding atmosphere grew misty, and they could smell an unmistakable odor of burning powder.
Soon another battery, farther to their right, began to fire. "How fortunate we did not get any further than this," said Gascon.
"Why?" asked Alfred, in astonishment.
"Because we should have run into another battery and encampment to the rear of this."
They were hardly settled in the temporary shelter, when they heard a peculiar hissing sound, and immediately felt, a peculiar shock as of a falling body, followed by an explosion of a huge shell which threw dirt and sand over them. This was really more terrifying to the boys than their experience at the mouth of the mine on the first day of their wanderings.
"That must have been awful close," said Alfred, with a perceptible tremor in his voice.
"It was fully fifty metres (163 feet) beyond us. That was, probably, an eight-inch shell, and if it had come within ten meters, (about 32 feet), of the battery the latter would have been put out of action."