A peculiarity of the Argentine climate in general is that the temperature will change very rapidly during the day, or even during a few hours; the change representing sometimes a difference of more than 36°, especially in the spring, which is the most usual season for these rapid variations. The climate of the coast region——that is, of a country consisting almost entirely of plains——is, in general, influenced by the winds, which blow in gales at all seasons. Northerly and southerly gales are the most common; the first especially are very frequent. In Buenos Ayres one finds, during the summer, an alternation of sea and land breezes; the one during the day, the other during the night. The northerly winds are always hot and even suffocating; they influence the nervous system, afflicting some people with neuralgic troubles. When these winds blow, the air is charged with electricity, until, the tension of the atmosphere having grown insupportable, a tempest comes to restore the equilibrium, to give place to another wind, coming from the south-west, and known as the _pampero_. This wind does not often last long, but it attains a velocity equal to that of a full hurricane. The _pampero_, so called because it is formed in the region of the pampas, is a wind full of ozone, and as such plays its part in disinfecting the vitiated air of the urban centres. But the effects of the _pampero_, and especially of the south-westerly winds, on the Rio de la Plata, where they produce a violent swell, are sometimes terrible. As for the rain, there is no regularity in its fall; which naturally tends to render the results of culture and of cattle-breeding variable. Rains are more frequent in summer and autumn than at other times; while the least rainfall is that of winter. At Buenos Ayres it is rare for a month to pass without rain, which is often torrential, and accompanied by hail. The climate of the central region, if we except the mountainous portions of the Provinces of San Luis and Córdoba, is distinguished from the seaboard region by its greater dryness and its sudden variations of temperature. In the plain the summers are very hot, and it is not uncommon to see the thermometer at 104°; while during the winter there are very hard frosts. As on the coast, northerly and southerly winds are the most frequent. Rain is rarer than on the coast, and falls almost exclusively in summer and in autumn: with rare exceptions the winter is perfectly dry. In the Andean region the climate varies according to the height above sea-level, but is always characterised by sudden variations in the daily temperature, and by excessive dryness. On the eastern slope of the Andes and the plateaux of the north it never rains. These regions are continually swept by furious winds, which make agriculture impossible. To the intense heat of the day succeeds the cold of the night, with differences of temperature that sometimes amount to 68° in twenty-four hours.