on the Marine Barometer. 
251 
4th. The month of September, 1802, and the greater part 
of August and October, we spent upon the east coast between 
the latitudes 23 0 and 17 0 . The south-east trade is the regular 
wind here, but we had many variations. Whilst the trade 
prevailed, the average standard of the mercury was 30,15, 
and the more southwardly it was, and the fresher it blew, the 
higher the quicksilver rose, though it never exceeded 30,30. 
When the trade wind was light, it was usual for a breeze to 
come off the land very early in the morning, and continue 
till eight or nine o'clock ; but these temporary land winds did 
not produce any -alteration in the mercury, which kept at 
these times about 30,10. When the trade wind veered round 
to ENE, or more northward, which was not seldom, the mer- 
cury ranged between 30 inches and 30,10 ; and when a breeze 
from north or N by W prevailed, which was the case for a 
considerable part of twenty days we remained in Broad 
Sound, its height was something, but not much, less. These 
northwardly winds I take to have been the north-east wind 
in the offing ; which had been partly turned, and in part 
drawn out of its direction, by the peculiar formation of this 
part of the east coast. There are but few instances of any 
steady westwardly wind prevailing; when such happened, 
they were generally from the north side of west; and at 
these times the range of mercury was between 29,95 and 
30,05, which was the lowest I at any time saw it on this 
portion of the east coast. 
The barometer was of great service to me in the investi- 
gation of this dangerous part of the east coast, where the ship 
was commonly surrounded with rocks, shoals, islands, or 
coral reefs. Near the main land, if the sea breeze was dying 
