ddition by a great
inland sea.
To many who travel over the State it seems a marvel that the atmosphere
should have any elasticity or any tonic properties.
It is, however, known that countries are usually dependent, for the
beneficent rains falling over them, on oceans quite remote, where the
sun, in its tropical splendor and power, lifts high in air immense
volumes of water in a state of evaporation, which, borne on the "wings
of the wind," speeds rapidly away to supply the drying rivers and
fountains of the globe. This aerial pathway supplies the link in the
great circuit by which all the waters of all the oceans pass over our
heads, returning again under our feet to their natural home.
Of course the water area of all sections of the temperate latitudes
contribute something to the precipitation; yet it is but a fractional
part of the whole, and quite inconsiderable. Still its influence is
sufficient to make it observable near large seas like our own inland
system, where the quantity falling is, in the cooler portions of the
year, increased in consequence of the then higher temperature of the
water of the lakes over that of the adjacent land districts. In summer,
the only effect is to increase the humidity of the atmosphere and
frequency of rains, without adding to the quantity. This phenomenon is
seen on the shores of all the lakes, and especially in the Lake Superior
region. But this influence does not extend westward to exceed the
distance of, we should say, fifty miles, and does not consequently
effect to any important degree the climate of Minnesota, except the
outlying rim described. The small lakes and rivers do not contribute
much to the precipitation of rain within the State boundaries. They may
add slightly to that of the lake district to the eastward, whither their
moisture is borne by the southwesterly and westerly currents. They do
undoubtedly have an influence on the temperature, modifying that of the
winter very much, and in this respect are valuable as well as beautiful.
The southerly winds, and those having a slight westerly tendency,
prevailing a portion of the summer, do not bring hither much of
moisture, though at their outset they are heavily ladened with it, as it
is borne across the Gulf, in a southwesterly direction, to the open
valley of the Mississippi, where, coming in contact with the edge of the
great westerly winds, and broken probably somewhat by the elevated
district of Mexico and
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