2 6s Mr. Flinders’s Observations 
upon the shore from the sea, it follows, that the mercury 
ought to stand something higher when such a wind blows, 
whether it is from the south or any other quarter, than it will 
with the same wind where it meets no such obstruction ; and 
the more direct it blows upon the coast, and the higher the 
land is, (all other circumstances being equal,) the higher 
ought the mercury to rise. On the other hand, when the 
wind comes from off the hills, this dead and dense air will be 
displaced, even from its hollows under the highest land ; 
both on account of its own expansion, and because its particles 
will be attracted by those of the air immediately above, which 
are taking their unobstructed course out to sea ; and thus the 
air over the coast will resume its natural state with a land 
wind. 
In order to appreciate duly the effect of sea and land winds 
upon the barometer, in the preceding examples, it is neces- 
sary to be recollected, that in the southern hemisphere, a wind 
from the south has a natural tendency to raise the mercury 
in the open sea, and one from the north to depress it; pro- 
bably, from the superior density of the air brought in by the 
former; therefore, if the mercury rises quicker and higher 
with a south wind upon the south coast, than it does with a 
north wind upon the north, it is not to be at once concluded, 
that the effect of the wind as coming from the sea, is less 
upon the north coast; for it has, in the first place, to coun- 
teract the tendency of the mercury to fall with a north wind; 
and in some cases, its effects as a sea wind may be as consi- 
derable, relatively to the latitude, where there shall be no 
rise in the barometer, as upon the south coast it might where 
a considerable one took place. The same thing may be said 
