They set to work with hearty goodwill, muffling their oars, and preparing for their noiseless advance into the harbour.

The guns would roar ceaselessly overhead.

That would do much to drown any sound from the water.

Still, care and caution would have to be exercised; for the batteries of the fortress commanded the harbour, and the ships lay beneath their protecting guns.

If the little flotilla betrayed its approach by any unguarded sound, it might easily be annihilated before ever it could approach its goal.