4 
Thickness of the Antarctic Ice , and its [January, 
and an open sea in another. We have not in the Antarctic, 
as in the Arctic region, well-marked warm and moist aerial cur- 
rents and cold and dry winds blowing athwart different areas. 
Surrounding the South Polar continent lies an unbroken 
ocean, in an almost uniform climatic condition. This region 
also, as Sir Wyville Thomson remarks, is “ continuously 
solid, — that is to say, it is either continuous land or dis- 
membered land fused into the continental form by a conti- 
nuous ice-sheet.” In this case we can treat it as one 
continuous continent. The South Pole being safely assumed 
to be in the centre of the sheet, we have here what we per- 
haps never had on the northern hemisphere even during the 
Glacial Epoch — a polar ice-cap. We have the pole in the 
centre of the cap ; therefore, at equal distances from the 
pole or centre, the conditions in every respedt, both as to 
climate and the thickness of the ice, may be assumed to be 
the same ; for no reason can be assigned for supposing the 
conditions in separate areas upon the same parallel of 
latitude to differ. Thus, as a purely physical and me- 
chanical problem, the conditions could hardly be more 
simplified. 
We shall now enter into the consideration of the question. 
In the first place, the conclusion that “ ice at the tempera- 
ture at which it is in contact with the surface of the earth’s 
crust within the Antarctic regions cannot support a column 
of itself more than 1400 feet high without melting ” is in 
diredt opposition to known fadts. 
The immense tabular icebergs found in the Southern 
Ocean, which have been so well described by Sir Wyville 
Thomson, are of course portions broken off the edge of the 
ice-sheet, and the thickness of the bergs represents the 
thickness of the ice-sheet at the place where they broke off. 
Now, some of these icebergs have been found to be more than 
three times the limit assigned by Sir Wyville. The 
following are a few out of the many examples which might 
be adduced of enormous icebergs, taken from the Twelfth 
Number of the “ Meteorological Papers ” published by the 
Board of Trade, and from the excellent paper of Mr. Towson 
on the “ Icebergs of the Southern Ocean,” published also 
by the Board of Trade. 
Sept. 10th, 1856. — The Lightning, when in lat 55 0 33' S., 
long. 140° W., met with an iceberg 420 feet high. 
Nov., 1839. — l at - 4 T ° S., long. 87° 30' E., numerous ice» 
bergs 400 feet high were met with. 
