There were good telescopes in the car, and the boys directed them upon the immense panorama below them.
"What fort is that, immediately beneath us?" Ralph asked.
"That is Vanves. The village you see there is Chatillon. Look out now, we may expect visitors, in a minute."
He had hardly spoken before they heard a faint sound, followed by others similar.
"That is musketry," Monsieur Teclier said. "Listen."
They did listen, and heard a peculiar whistling sound; which seemed below, around, and about them.
"That is a whistle of bullets; there is no mistaking them," Ralph said.
"We are too low," Monsieur Teclier said. "Throw out that bundle of newspapers; we will go up a little."
Ralph did so.
"What would be the consequence, if a bullet hit the balloon?"