On the morning of the 20th of June they cast their lines off the coal dock, the big Diesels turned over smoothly, and the Neptune backed away and turned its nose toward the open bay.
As many of the crew of 31 as could crowd onto the deck watched the changing scene, and listened to the wishes for good fortune shouted by the townspeople on the dock. There was a fresh breeze in the outer bay and they were forced below by the crisp wind which sent waves slapping over the deck in steady succession.
They were in the land of the midnight sun where in summer there is no night, only a dusk as the sun dips to the horizon. At dusk the mainland of Spitzbergen was to the rear and they were slipping past Amsterdam island, which lay to their right. Ahead of them was the uncharted mystery of the Arctic ocean.
Harry was surprised at the comparative mildness of the Arctic summer but the temperature of the Arctic sea was not such that a fall overboard was inviting and as a result the outer hull of the craft was ice-cold. Special electrical heating devices had been installed in the living quarters and the control room so it was fairly comfortable inside the sub.
As they pushed northward, Gilbert Mathews and the two scientists with him kept busy in the forward torpedo room where they made soundings of the ocean depth and drew off samples from the bottom to determine the nature of the floor of the Arctic. Because of the scientific investigations, the Neptune made slow progress and it was the fourth day out before they encountered much pack ice.
Conditions were favorable for the progress of the Neptune, for the ice fields were open with wide leads between them. Occasionally a small berg scraped the side of the submarine and on the fifth day, when they encountered a solid mass of ice, the diving order was given and the Neptune, its special electrical feelers projecting ahead, slipped under the wall of ice and into the open water on the other side. Such an operation was under the direct charge of Bob Smith, who demonstrated his ability in that one brief maneuver.
The weather remained fair and on the 26th and 27th, the Neptune increased its speed for the ice was fairly open. They were following almost the same route taken by Byrd and Bennett in their successful dash by air to the North Pole. On the twenty-eighth the sky closed in on them. A cold Arctic fog obscured the sun and a wall of static shut them off from communication with the outside world. They were now well into the unknown regions of the Arctic, further north than any vessel had previously penetrated, in the region which had been seen by man only from the air.
On the night of the twenty-eighth a bitter wind whipped down out of the northwest and the leads commenced to close under the pressure of the drifting ice. The Neptune scuttled from one open area to another seeking safety but the gravity of the situation increased every minute. With the ice pack closing in, it was possible that the submarine might be caught between the ice and crushed like an egg shell for despite its sturdy construction it could not withstand the enormous pressure which the ice would exert.
Bob was glued to the controls while Gilbert Mathews searched madly for an opening through which the Neptune might slip to safety. There was none and reluctantly the order was given to submerge.
They would be safe down below for the time being but they would be unable to tell in what direction safety lay. They would have to feel their way almost blindly under the ice, hoping that they would eventually find an opening where they could rise to the surface.