It had grown sensibly darker, but the line of mist had not risen higher. Harry remarked upon this.
"I almost doubt whether it is coming after all," he said.
The captain shook his head.
"It does not spread over the sky," he said, "because it is largely dust blown off the land. After the first burst you will see that we shall have a bright blue sky and a roaring wind, just as one gets it sometimes in an easterly gale in the Channel. We shall have it in another five minutes, I fancy. I don't think it will be very strong, or we should have had it here before this."
It was not long before a dull, moaning sound was heard, the brown-red fog changed its appearance, swirls of vapour seemed to dash out in front of it, and the whole swelled and heaved as if it were being pushed forward by some tremendous pressure in its rear.
The ship's head was pointing nearly east, the canvas hung down motionless, and there was not a breath of wind.
"Hold on all!" the captain shouted. Half a minute later the billowly clouds swept across the vessel, and a sudden darkness overspread them. Then there was a glow of white light, a line of foam approached as fleet as a race-horse, and with a shriek the gale was upon them. The vessel shook from stem to stern as if she had struck against a rock, and her bow was pressed down lower and lower until she seemed as if she were going to dive head-foremost. But as she gathered way, her bow rose, and in a minute she was flying along at some eighteen knots an hour.
"She is all right now, Mr. Prendergast," the captain said. "It is well we stripped her so thoroughly, and that she is not heavily laden."
Four men had been placed at the wheel, and it needed all their strength to keep her from yawing. In half an hour the sea began to get up, and the captain laid her course south-east, which put the wind on her quarter.
"It is well we were not a degree or so farther south, Captain."