Confining our view to South America, we should certainly be tempted to
believe that trees flourished only under a very humid climate; for the
limit of the forest-land follows, in a most remarkable manner, that of
the damp winds. In the southern part of the continent, where the
western gales, charged with moisture from the Pacific, prevail, every
island on the broken west coast, from lat. 38 degs. to the extreme
point of Tierra del Fuego, is densely covered by impenetrable forests.
On the eastern side of the Cordillera, over the same extent of
latitude, where a blue sky and a fine climate prove that the atmosphere
has been deprived of its moisture by passing over the mountains, the
arid plains of Patagonia support a most scanty vegetation. In the more
northern parts of the continent, within the limits of the constant
south-eastern trade-wind, the eastern side is ornamented by magnificent
forests; whilst the western coast, from lat. 4 degs. S. to lat. 32
degs. S., may be described as a desert; on this western coast,
northward of lat. 4 degs. S., where the trade-wind loses its
regularity, and heavy torrents of rain fall periodically, the shores of
the Pacific, so utterly desert in Peru, assume near Cape Blanco the
character of luxuriance so celebrated at Guyaquil and Panama. Hence in
the southern and northern parts of the continent, the forest and desert
lands occupy reversed positions with respect to the Cordillera, and
these positions are apparently determined by the direction of the
prevalent winds. In the middle of the continent there is a broad
intermediate band, including central Chile and the provinces of La
Plata, where the rain-bringing winds have not to pass over lofty
mountains, and where the land is neither a desert nor covered by
forests. But even the rule, if confined to South America, of trees
flourishing only in a climate rendered humid by rain-bearing winds, has
a strongly marked exception in the case of the Falkland Islands. These
islands, situated in the same latitude with Tierra del Fuego and only
between two and three hundred miles distant from it, having a nearly
similar climate, with a geological formation almost identical, with
favourable situations and the same kind of peaty soil, yet can boast of
few plants deserving even the title of bushes; whilst in Tierra del
Fuego it is impossible to find an acre of land not covered by the
densest forest. In this case, both the direction of the heavy gales of
wind and of the currents of the sea are favourable to the transport of
seeds from Tierra del Fuego, as is shown by the canoes and trunks of
trees drifted from that country, and frequently thrown on the shores of
the Western Falkland. Hence perhaps it is, that there are many plants
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