MO AMSTERDAM ISLAND. 
ward of tlie Cape, v/as 245 miles in 24 hours, or IO-L nearly 
in each hour. The prevailing southerly winds in these lati- 
tudes, during the summer months, are no doubt occasioned 
by a strong current of condensed air rushing from regions of 
ice towards the more rarefied atmosphere of Southern Africa ; 
where the vapour with which it is loaded, by a change of 
temperature, and by concussion against the high mountainous 
promontory of the Cape, is discharged ; and subsides in that 
singular fleecy cloud which envelopes the summit of the 
Table mountain, continuing for several days together when- 
ever the south-easterly wind prevails. 
On the 1st of February we discovered the two islands of 
St. Paul and Amsterdam, and on the evening of the same 
day anchored on the eastern side of the latter, at the distance 
of about a mile from the shore. The volumes of smoke 
which we had perceived at a distance to ascend from the 
island, and the flames which, when dark, were seen dis- 
tinctly to issue from it, excited in us a strong desire to get 
on shore ; and accordingly before it was well light the next 
morning we quitted the vessel, elate with the hope of gratify- 
ing curiosity by some novel spectacle. Of the result of our 
observations the following is a brief sketch. The island of 
Amsterdam, which lies in latitude 38° 42' south, and longi- 
tude 76° 51' east, is, in its greatest extent, about four miles 
and a (juarter from north to south, and two and a quarter 
from east to west, containing seven or eight square miles of 
surface, exclusive of a large volcanic crater, into which the 
sea has forced a passage on the eastern side, by the incessant 
action of its waves rolling with an uninterrupted current from 
