THE NARRATIVE OF .CHARLES;| WILKES, 411 
counter-current to maintain the level of the waters. These masses, then, 
are most probably carried away in the seasons when the polar streams 
are the strongest, and are borne along by them at the velocity with which 
they move ; that these do not oceur annually may be inferred from the 
absence of ice-islands in the lower latitudes; and that it is not from the 
scarcity of them those who shared the dangers of the Antarctic cruise 
will, I have little doubt, be ready to testify ; for, although great numbers 
of them studded the ocean that year, yet the narrative shows that vast 
numbers of them were left. 
The specific gravity of the ice varies very much, as might naturally 
be expected; for while some of it is porous and of a snowy texture, 
other islands are in great part composed of a compact blue, flinty ice. 
This difference is occasioned by the latter becoming saturated with 
water, which afterwards freezes. 
On the ice there was usually a covering of about two feet of snow, 
which in places had upon it a crust of ice not strong enough to bear the 
weight of a man. Those ice-islands, which after having been once seen, 
were again passed through immediately after a gale, were observed to 
be changed in appearance; but though for forty-eight hours a severe 
storm had been experienced, they had not undergone so great a trans- 
formation as not to be recognised. They also appeared to have shifted 
their position with regard to one another, their former bias and trendiugs 
being broken up. 
During our stay on the icy coast I saw nothing of what is termed 
pack-ice—that is, pieces forced one upon the other by the action of the 
sea or currents. 
On the 21st the weather became unsettled, with light westerly winds, 
and we made but little progress to the westward. The barrier, at 6 p.m., 
was seen trending to the westward. In consequence of indications that 
threatened bad weather, I deemed it useless risk to remain in the 
proximity of so many ice-islands, and a strong breeze, with squally 
weather, having already set in, I took advantage of it, feeling satisfied 
that our farther continuance in this icy region would not only be at- 
tended with peril to the ship, but would cause a waste of the time which 
was demanded by my other duties; and having nearly 8000 miles to 
gail to our next port (Bay of Islands), I made up my mind to turn the 
head of the vessel northward. 
I therefore had the officers and crew called aft, thanked them all for 
their exertions and good conduct during the;trying scenes they had gone 
through, congratulated them on the success that had attended us, and 
informed them that I had determined to bear up and return north. 
Having only twenty-five days’ full allowance of water, I ordered its 
issue to be reduced to half allowance. 
I have seldom seen so many happy faces, or such rejoicings, as the 
announcement of my intention to return produced. But although the 
