AS OBSERVED IN THE WEDDELL SEA. 
811 
over a year old ; as floes and brash it had been the cause of the ship’s being beset in 
January 1915, and it was cemented at that time into what may be termed an “ice- 
conglomerate.” Its age and structure made it less liable to crack than young-ice, 
there being no vertical lines of weakness, so that a ship enclosed in such a position 
had all the appearance of security. Across this old ice to the frozen lead ahead a 
track ran from the ship for a distance of 300 yards, and was marked by cairns of ice- 
blocks, or pylons, as they were called. 
On the 22nd of J uly heavy pressure was taking place beyond the farthest of these 
pylons, and it led to the destruction of a couple of places where the ice had been till 
then a subject of weekly investigation. The impact of the pressure caused a crack 
the same afternoon in the old-ice round the ship — a “ shock crack,” which ran 
parallel to and roughly 40 yards distant from the pylon road. On the 23rd pressure 
still went on, and a ridge was formed built up of the youngest ice. The old-ice, 
however, and the 3 feet thick young-ice formed since February had not begun to raft, 
though some more shock cracks were developed in both. On the 24th the pressure 
ridge had advanced another 10 yards over, but not involving, the 3 feet thick ice of 
February. 
It was not, however, till the next day that the thicker ice, both that formed in 
February and that surviving from 1914, became involved. The already mentioned 
pressure ridge dating from the 22nd began an irresistible advance over the old-ice, 
weighing it down and breaking it up by means of “weight cracks.” Though it was 
not really necessary, one almost felt impelled to walk fast or even to run in order 
to avoid the advancing pressure. On the 26th there was a respite, and any further 
movement took the form of shearing. Matters, in fact, remained quiet until the end 
of the month. 
On the 1st of August, however, there being a strong S.S.W. blizzard blowing, new 
and unexpected developments took place. Not only did a crack form athwartships, 
running out at right angles to the ship on either beam, but a shock crack due to 
renewal of the July pressure started only 10 yards away on the starboard side. 
Working immediately set in along the latter crack, and blocks of ice 4 and 5 feet 
thick were soon involved in the pressure. The ship broke out of her ice-berth, and 
so rapidly did the shearing develop to starboard that it gave her the appearance 
of sailing over the top of the ice-floes. When in the afternoon things became 
quieter, the ship, instead of being safely bedded in an old conglomerate floe and 
300 yards from the February lead ahead, found herself right in the middle of broken- 
up and unstable ice, where trouble might always occur. 
This, however, was the end of the disturbances in the immediate neighbourhood, 
and the ship was once more frozen in, this time among a maze of hummocks and 
pressure ridges. 
The tendency in the next two months was for the pack to become looser, and 
unfrozen pools and lanes were not infrequent in October. On October 15, by 
TRANS. ROY SOC. EDIN., VOL. LII, PART IV (NO. 31). 126 
