The professor went to his bunk, and Mark was pleased enough to be left alone in charge of the ship. He held the wheel firmly, and did not deviate half a point from the northern course. He had been steering for half an hour when he was suddenly aware of a dense gloom that settled down all about him. Then there came a great roaring sound. The air craft rocked violently. The wind whistled shrilly through the cordage and careened the _Monarch_ to one side. Then the whole atmosphere grew from a dense black to a strange opaque whiteness: a whiteness that shut out the view from every side, and enveloped the ship as if it had fallen into a feather bed. Mark started back in fright and let go his hold on the steering wheel. CHAPTER XIX A BLINDING SNOWSTORM "Quick! Professor!" cried Mark. "Jack, Washington, everybody! Hurry up!" "What's the matter?" asked the inventor, running to the conning tower. In answer Mark pointed outside. "A snow storm!" exclaimed the captain. "We must expect them up north. But this is worse than I thought!" He glanced ahead. Nothing could be seen but a wall of white. The wind increased until it blew with almost the force of a cyclone, and the ship swayed fearfully. "Stop the engines!" cried the professor. "We had better drift than run the chances of hitting an iceberg if we should suddenly take a drop down to the ground." Washington, awakened from his sleep, turned off the power. Then began a fight between the ship and the elements; a battle between the _Monarch_ and the wind and snow. Which was to win? The airship was, apparently, in the heart of the storm. It was tossed this way and that, now up and now down, though because of the quantity of gas in the bag the craft was buoyed up. The gas generating machine had not been stopped, only the machinery that moved the propeller. How the wind howled! How the snow blew! It was a blinding storm, for from the windows of the conning tower and from those on either side of the cabin nothing could be discerned five feet away. Through the window in the bottom of the ship nothing showed but a sea of white flakes. The cold was intense, seventy degrees below zero being marked on the thermometer. Even with the gasolene stoves going it was chilling inside the airship, for the cutting, biting wind found many cracks through which to enter. But, if the propeller no longer urged the ship on, the force of the wind sent it ahead at a fearful pace. The gale careened the _Monarch_ from side to side. Now the bow would be elevated, and, again, the stern. It was like a ship on a rough sea, and the occupants of the craft were tossed from side to side, receiving many bruises. Old Andy was tied into his bunk, or he never could have stayed there, so violent was the motion. "Where is Dirola?" asked Mr. Henderson suddenly. "She was out on the stern a while ago," answered Bill. "She was saying something about it being too hot for her inside. That was before the storm came up."