It has been xecommended to invalids, especially to those of a consumptive habit, to reside at Pisa during the winter season ; at the baths of Pisa, or the city of Florence, during the first part of summer : and, during the great heats of midsummer, at the country retreats on the hills beneath Fie sole.
It has been imagined, that the climate of Italy has be come warmer that the descriptions by the ancient Romans would lead us to suppose it to have been in their time ; and this change has been ascribed to the cultivation of Germany, by the clearing away of its immense forests, and the drain ing of its extensive swamps. But the lofty barriers of the Alps seem to preclude any cause of this kind from operat ing upon Italy ; and others consider this higher tempera ture as the effect rather of earthquakes, volcanic eruptions, and similar local causes. It may be questioned, however; whether any change at all has taken place ; and it is ob served by travellers, that the same places which are de by the Roman writers as peculiarly cold, are still liable, in consequence of their situation, to severe winter blasts. But-the most remarkable peculiarity in the climate of Italy, is the Mal-Aria, or unhealthy state of the districts called Maremma, in the summer and autumn months. This tract extends about 192 geographical miles in length, from LeghoYn to Terracina, and about 40 in its greatest breadth in the Campagna di Roma. There is no visible sign of any insalubt ity in the atmosphere of these regions; but the sky is as clear, the air as tranquil, and the verdure as fresh as in the most healthy district. Many of the places where it prevails, are even elevated, dry, and airy. But nothing can be more fatal than its influence, which occasions the worst kind of intermittent fevers, and is particularly hurtful to those who sleep in the open air during the night. The few inhabitants who remain in these tracts, are sickly and languid in their whole appearance; and even those who re pair only to the temporary labours of the harvest, very fre quently fall a sacrifice to the distemper, or at least have their constitutions seriously injured for life. Even in the
vicinity of Rome, the shepherds and their flocks come eve ry night during summer to take shelter within the walls from the noxious atmosphere of the adjoining country. The city itself is not free from the evil, and even its more elevated situations have begun to experience the influence of this spreading insalubrity. To this increasing action of the mal-aria, the diminished population of Rome during the last 20 years is, in the opinion of Chateauvieux, to be in a great measure ascribed ; and the most fatal consequences must attend its Farther progress. The real cause of this evil has hitherto escaped all research, and has been ascrib ed to the pestilential air of the stagnant marshes, or the ex halations of a volcanic soil. But it is not confined to the places more immediately exposed to such influences ; and is found to increase with the diminution of the population, and the decay of cultivation. It appears to have been felt in the times of the Roman republic, but to have been limit ed to a few inconsiderable spots. The destruction of the Roman empire, the abolition of slavery by the influence of Christianity, the translation of the seat of government to Constantinople, by diminishing the cultivation of the sur rounding country, are supposed to have occasioned that neglected state of the soil which produces the malaria; while the influence of the evil itself is gradually augment ing the cause, depopulating the fields, and leaving the soil to fall back into its naturally rank and humid state. It has, at the same time, been observed, that much of the sickness is occasioned by the peasantiy, employed in these regions, sleeping on the ground during the night season, and ne glecting to protect themselves from the sudden transition of the atmosphere, from the heat of the day to the chill of the evening; and that, if the lands were portioned out in small farms, propel houses built for the cultivators, and prudent precautions used during the unwholesome season, the Maremma might again be brought into tillage, and co vered with inhabitants.
Soil and Agriculture.