318 On Malaria. 



which, by changing hands, and falling into the possession of non- 

 resident proprietors, have become dangerous as places of residence, 

 and are sinking in value every day. This results from the neglect of 

 ditches and low grounds, and the consequent encroachment of bogs 

 and marshes upon the borders of meadows, as these increase the 

 extent of plashy surface, and accumulate a mass of deadly materials 

 in weeds and herbage ; because tenants and hired laborers cultivate 

 only such parts as yield a ready profit. But this practice will be 

 found ruinous ; for where point by point is yielded, and the inhabit- 

 ants recede, the result will be as in Italy, a complete depopulation : 

 for, as I shall further shew, its destructive influences are in the in- 

 verse ratio of the resistance made by cultivation, and the habits of 

 civilized life. 



Perhaps I cannot in any way so concisely illustrate this point, as 

 by giving a history of its effects in Italy. 



The maremma of Tuscany extends from tlie south border of the 

 vale of the Arno, to the States of the Church, and from the Appe- 

 nines to the sea shore on the west. It was anciently covered 

 with a busy race of men, high in rank among heroes and sages : 

 but although its soils and seasons were then the same as now, 

 the insalubrious elements were probably kept in comparative sub- 

 ordination. Maremma signifies the region of malaria, and this 

 maremma has been cited as a proof that marsh effluvia cannot be 

 the source of malarious fevers, because this tract is nearly depop- 

 ulated by the diseases attributed to that cause, although it is an undu- 

 lating upland country, of volcanic origin. But perhaps it will be es- 

 teemed conclusive evidence that science has discovered the lurking 

 places of this poison, and that it conceals itself at times in spots re- 

 mote from the shaking morass and mangrove sea beach, although 

 those are its legitimate places of abode. In the valleys of this de- 

 serted tract, there are a few scattered houses, and the inmates, pale 

 and languid, appear to maintain but a feeble conflict with the de- 

 stroyer. On the hills are seen occasionally ruins of mouldering 

 towns and ancient towers ; " above all the rest rises the emi- 

 nence on which the aged walls of Volterra repose. Its inhab- 

 itants wander like shades among its majestic ruins, and do not 

 attempt to preserve even their habitations ; but abandon them to tJie 

 elements, and await with resignation " the returns of the scourge 

 which decimates them every year." 



