canyon may be traversed between icy walls 6 ft. to 10 ft. high, or a dome may be formed that under renewed pressure bursts upward like a volcano.  All the winter the drifting pack changes—­grows by freezing, thickens by rafting, and corrugates by pressure.  If, finally, in its drift it impinges on a coast, such as the western shore of the Weddell Sea, terrific pressure is set up and an inferno of ice-blocks, ridges, and hedgerows results, extending possibly for 150 or 200 miles off shore.  Sections of pressure ice may drift away subsequently and become embedded in new ice.

I have given this brief explanation here in order that the reader may understand the nature of the ice through which we pushed our way for many hundreds of miles.  Another point that may require to be explained was the delay caused by wind while we were in the pack.  When a strong breeze or moderate gale was blowing the ship could not safely work through any except young ice, up to about two feet in thickness.  As ice of that nature never extended for more than a mile or so, it followed that in a gale in the pack we had always to lie to.  The ship was 3 ft. 3 in. down by the stern, and while this saved the propeller and rudder a good deal, it made the ‘Endurance’ practically unmanageable in close pack when the wind attained a force of six miles an hour from ahead, since the air currents had such a big surface forward to act upon.  The pressure of wind on bows and the yards of the foremast would cause the bows to fall away, and in these conditions the ship could not be steered into the narrow lanes and leads through which we had to thread our way.  The falling away of the bows, moreover, would tend to bring the stern against the ice, compelling us to stop the engines in order to save the propeller.  Then the ship would become unmanageable and drift away, with the possibility of getting excessive sternway on her and so damaging rudder or propeller, the Achilles’ heel of a ship in pack-ice.

While we were waiting for the weather to moderate and the ice to open, I had the Lucas sounding-machine rigged over the rudder-trunk and found the depth to be 2810 fathoms.  The bottom sample was lost owing to the line parting 60 fathoms from the end.  During the afternoon three adelie penguins approached the ship across the floe while Hussey was discoursing sweet music on the banjo.  The solemn-looking little birds appeared to appreciate “It’s a Long Way to Tipperary,” but they fled in horror when Hussey treated them to a little of the music that comes from Scotland.  The shouts of laughter from the ship added to their dismay, and they made off as fast as their short legs would carry them.  The pack opened slightly at 6.15 p.m., and we proceeded through lanes for three hours before being forced to anchor to a floe for the night.  We fired a Hjort mark harpoon, No. 171, into a blue whale on this day.  The conditions did not improve during December 19.  A fresh to strong northerly breeze brought