62 Meteorological Sketches. 
wind blows in a direction more towards the equator than in its cen- 
tral or western portions. 
In the higher latitudes north of 30°, the westerly winds are found 
greatly to predominate, although the eddying or rotative action which 
is acquired by large portions of the lower stratum of air in these lat- 
itudes, causes much diversity and frequent changes in the specific 
direction of the local winds. But in the common region of clouds, 
where this eddying movement is less frequent, the main atmospheric 
current, at least in the United States, is fully as constant from the 
westward, as is the trade wind from the eastward in any tropical 
region. 
_ At New York, in four successive years the westerly winds have 
been found to be to the easterly, as nearly as two to one. Observa- 
tions on the courses of the clouds for the same period, show the prev- 
alence of an atmospheric current from the westward at that elevation 
to be, as compared with those from the eastward, nearly as fourteen 
to one; the prevailing wind being southwesterly. At Montreal, in 
Lower Canada, as appears by the observations of J. M’Cord, Esq. 
the westerly surface winds also appear to exceed the easterly, in the 
proportion of more than four to one. In consequence of the general 
prevalence of westerly winds and currents in these latitudes, the 
passages of the fastest ships, from Europe to America, are found to 
occupy a much longer period than from America to Europe. 
he first movement of the trade winds towards the equator and 
westward, necessarily occasions an equal movement from the higher 
latitude to supply their place ; and as the trade winds in their pro- 
gress westward are opposed by the American and Asiatic continents, 
across which these winds do not pass, it follows that these winds be- 
come deflected or thrown off towards the poles in order to support 
an equal distribution of the atmosphere in the higher latitudes ; but 
the air thus transferred to these latitudes carries with it the rotative 
impulse which it acquired in the tropical latitudes, and by reason of 
the slower rotative motion which here ase roe is thrown to the east- 
ward in the form of westerly winds. 
An entire circuit of atmospheric currents is thus maintained on 
both sides of the equator, the most equable and determinate portion 
of which is to be found in the region of the trade winds; and this 
appears to be the general outline of the great system of circulation 
in Our atmosphere, as well as in the ocean itself. It is to the geo- 
graphical course pursued by the winds in different portions of these 
