The vessel now found herself in the middle of the Bering Sea pack ice. Here and there were open leads still, but they were fewer, more narrow, and much less connected. Now and again there were places where contrary winds and currents had crushed the floes together, piling the crumpled cakes high on one another in wild confusion, often to a height of twenty or thirty feet. Joe called these hummocks icebergs, and Harry and he had much friendly controversy as to the correct use of that term. Harry explained that he had learned that icebergs were the product of glaciers alone, that there were no glaciers on the Alaskan coast north of the Aleutians, and that these should properly be called hummocks. In this he was right, but Joe, with the pride of the man who “has been there,” would not concede it. Whatever they were, they totally prevented the progress of the vessel, and when they appeared in the path, the Bowhead was obliged to make a detour to avoid them. Now and then they were obliged to “buck ice” to get from one lead to another, and the process was very exciting. The vessel under a full head of steam would plunge straight at the field of heavy ice, striking it with a thump that entirely stopped progress and shook the structure from stem to stern. The masts would spring under the blow, and at each shock Harry fully expected to see Captain Nickerson jolted from his perch in the crow’s nest, high on the fore-mast. Then the ship would back away again at the captain’s order, leaving a three-cornered dent in the ice. Again and again she would rush at this dent with her great weight under full head of steam, till the floe would split, and leave a narrow crack through which the vessel could crowd her way. Thus for several days they hammered their way on through the pack, until they reached its northwestern edge, where open water gave them free passage to the ice-bound shores of east Siberia. There they came to anchor under a headland, and though it was mid-June and did not seem cold, were greeted by a storm of snow that came scurrying down from the snow-clad hills inland. [Illustration: BUCKING THE ICE]