on the Marine Barometer. 263 
of the winds from the east and from the west ; for where the 
vicinity of land is out of the question, the former generally 
causes an ascent, (from what principle I leave others to de- 
termine,) and the latter a descent in the barometer, and I 
believe this extends to both hemispheres, and all climates. 
The wind from SE then, which combines something more 
than half the power, both of the south and of the east wind, 
will raise the mercury higher than any other, on the south 
side of the equator, and the wind from NW permit it to fall 
lower, independently of their effects as sea and land winds ; 
and this allowance requires to be first made upon them : the 
south-west and north-east quarters should be equal where 
there is no land in question, and of a medium strength be- 
tween the power of the south-east, and the deficiency of the 
north-west wind. 
I leave it wholly undetermined, whether the effects of sea 
and land winds upon the barometer, as above described, ex- 
tend beyond the shores of the country where these observa- 
tions were made, and to about one hundred leagues of distance 
from them ; but it seems not improbable, that they may be 
found to take place near the shores of all countries similarly 
circumstanced ; that is, upon those which are wholly, or for 
the most part, surrounded by the sea, and situated within the 
fortieth degree of latitude. In colder climates, where snow 
lies upon the ground during a part of the year, the wind 
from off the land may perhaps be so cold, and the air so much 
condensed, as to produce a contrary effect; but this, and the 
prosecution of the subject to other important consequences, I 
leave to the philosopher ; my aim being only to supply my 
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