On Saturday night, the 24th [April 1858], I went on deck to spend the greater part of it watching, and to determine what to do. The swell greatly increased; it had evidently been approaching for hours before it reached us, since it rose in proportion as the ice was broken up into smaller pieces. In a short time but few of them were equal in size to the ship's deck; most of them not half so large. I knew that near the pack-edge the sea would be very heavy and dangerous; but the wind was now fair, and, having auxiliary steam-power, I resolved to push out of the ice if possible. . . . The shocks of the ice against the ship were alarmingly heavy; it became necessary to steer exactly head-on to swell. We slowly passed a small iceberg 60 or 70 feet high; the swell forced it crashing through the pack . . . Much hummocky ice and large berg-pieces lay dispersed through the pack; a single thump from any of them would have been instant destruction. By five o'clock [morning of the 25th] the ice became more loose, and clear spaces of water could be seen ahead. We went faster, received fewer though still more severe shocks, until at length we had room to steer clear of the heaviest pieces; and at eight o'clock we emerged from the villainous "pack," and were running fast through straggling pieces into a clear sea. [M'Clintock, pp. 105-107. ]