general scarcity of wood. Among the introduced kinds may
be enumerated poplars, olives, peach, and other fruit trees:
the peaches succeed so well, that they afford the main supply
of firewood to the city of Buenos Ayres. Extremely level
countries, such as the Pampas, seldom appear favourable to
the growth of trees. This may possibly be attributed either
to the force of the winds, or the kind of drainage. In the
nature of the land, however, around Maldonado, no such
reason is apparent; the rocky mountains afford protected
situations; enjoying various kinds of soil; streamlets of
water are common at the bottoms of nearly every valley;
and the clayey nature of the earth seems adapted to retain
moisture. It has been inferred with much probability, that
the presence of woodland is generally determined [2] by the
annual amount of moisture; yet in this province abundant
and heavy rain falls during the winter; and the summer,
though dry, is not so in any excessive degree. [3] We see nearly
the whole of Australia covered by lofty trees, yet that country
possesses a far more arid climate. Hence we must look
to some other and unknown cause.

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