On the Malaria of the Campagna di Roma. 119 



passing from them. These two causes combined prevent putre- 

 faction. 



The learned Moscati thinks he has discovered that the basis 

 of the foul air which causes these pestilential fevers, is an aque- 

 ous humour, which contains an animal mucus in which the ve- 

 nom resides. Brocchi has made some experiments upon the 

 nature of the malaria. He selected for this purpose the country 

 which surrounds the basilica of St Laurent, without the walls, 

 one of the most unhealthy of Rome, and continued his labours 

 during several successive nights. A robust young man, whom 

 he took for his assistant, slept several hours during the first 

 night, and was seized the following morning with an intermit- 

 tent fever, which he retained for several weeks. Brocchi con- 

 densed, in various ways, the air which he had collected, and ob- 

 tained, in every case, a notable quantity of putrid water. 



It remains for us to say a few words on the manner in which 

 this foul air acts upon the animal orgaraization. With respect 

 to the mode by which it penetrates our bodies, Brocchi has seve- 

 ral reasons for thinking that it penetrates rather by the pores of 

 the skin than by respiration. When once the noxious particles 

 are introduced into our organs, they combine with the humours ; 

 the general organization, or more properly the force which 

 tends to preserve it in its integrity, opposes this combination, 

 and from this results the fever. 



It is worthy of remark, that this foul air exerts no evil in- 

 fluence over the flocks which ramble night and day over the 

 Campagna di Roma. This would seem to justify the idea that 

 it penetrates by the pores of the skin, since these animals are 

 defended by their hair or their wool; and hence we perceive a 

 new proof that the best means which the ancient inhabitants 

 of Latium employed as a defence against this pernicious atmo- 

 sphere, before an excellent state of cultivation had weakened its 

 effects, was precisely the same kind of woollen clothing; so that 

 the dress of the present age is very ill adapted to a country 

 where an insalubrious atmosphere constantly prevails. 



