The roar of machinery was clearly audible.

From the house came the mingled shouting of many voices.

Something dropped into the sea a hundred yards away with a screech and a hiss, and a geyser-like fountain leapt so high that the spray reached them.

Then there was a sharper sound as a rifle bullet whistled by.
"My God!" Granet exclaimed.

"It's time we were out of this, Collins!" He seized his scull.