A prolonged, intense, sibilant buzzing in the apparatus, and--nothing!...
Absolute silence.
The operator now on duty responded with negative movements to his companion's inquiring glances.

He could hear nothing but the dialogue between the boats that had received the same warning.

They too were alarmed by the sudden silence, and were changing their course going, like the French steamer, toward the place where the _Californian_ had met the submersible.
"Can it be that they are already in the Mediterranean!" the operator exclaimed with astonishment on finishing his report.

"How could the submarines possibly get 'way down here ?..." Ferragut did not dare to go up on the bridge.

He was afraid that the glances of those men of the sea might fasten themselves accusingly upon him.