One thing only was satisfactorily done. An immense iceberg lay off the harbor, and I had the measurement of it in my note-book, and a sketch of it in my portfolio. The square wall which faced toward my base of measurement was three hundred and fifteen feet high, and a fraction over three quarters of a mile long. The natives told me that it had been grounded for two years. Being almost square-sided above the sea, the same shape must have extended beneath it; and since, by measurements made two days before, I had discovered that fresh-water ice floating in salt water has above the surface to below it the proportion of one to seven, this crystalized piece of Eric's Greenland had stranded in a depth of nearly half a mile. A rude estimate of this monster, made on the spot, gave me in cubical contents about twenty-seven thousand millions of feet, and in weight something like two thousand millions of tons. I leave the reader to calculate for himself its equivalent in dollars and cents, were it transported to the region of ice-creams and sherry-cobblers, and how much of it would be required to pay off the national debt, and how much more than half a century it would withstand the attacks of the whole civilized world upon it, for all those uses to which luxury-loving man puts the skimmings of the Boston ponds. [Sidenote: HEADING FOR MELVILLE BAY.] The tide at length carried off the ice which imprisoned us, and in the evening of the 22d we were again threading our way among the bergs and islands. Cape Shackleton and the Horse's Head lay off the starboard bow, and we were shaping our course for Melville Bay. [Illustration] CHAPTER VI. ENTERING MELVILLE BAY.--THE MIDDLE ICE.--THE GREAT POLAR CURRENT--A SNOW STORM.--ENCOUNTER WITH AN ICEBERG.--MAKING CAPE YORK--RESCUE OF HANS. The sun was now no longer above the horizon at midnight, and the nights were growing gloomy, a circumstance which warned us to additional carefulness. Notwithstanding our precautions, we narrowly escaped running upon a sunken reef which lies off the Horse's Head, and is not laid down on the chart. We came also among some ice-fields, the first that we had yet encountered. The waves were rolling in threateningly from the southwest, and the ice, tossing madly upon them, gave us an uncomfortable sense of insecurity; but we escaped into clear water after receiving a few thumps which did no material damage to our solid bows. By eight o'clock in the morning we had Wilcox Point clearly in view, and the Devil's Thumb loomed above a light cloud which floated along its base. Before us lay Melville Bay. Climbing to the fore-yard, I swept the horizon with my glass;--there was no ice in sight except here and there a vagrant berg. To the westward an "ice-blink" showed us that the "pack" lay there; but before us all was clear,--nothing in sight but the "swelling and limitless billows."