234- M. Paul Savi's Considerations 07i the 



various regions of the south of Italy are afflicted witli the 

 scourge described in the country by the names of cattlv^ aria 

 and mal aria (bad air), common language thus appearing to 

 attribute the morbid effects to the constitution of the atmo- 

 sphere in these localities. Examinations into the causes of 

 the unhealthiness of various regions of the Tuscan soil have 

 previously occupied several philosophers, and the author of 

 this memoir has endeavoured to throw light on this important 

 question at a period in which the generous efforts of the sove- 

 reign are directed towards improving the salubrity of these 

 localities. 



M. Savi readily admits that he is not prepared to propose 

 a remedy for the scourge: the object of his memoir, which is 

 principally geological, is to review the different unhealthy lo- 

 calities, to examine carefully the constitution of their soil, and 

 particularly to describe those regions in which the unhealthi- 

 ness appears not to result from the usually admitted causes, 

 in order to discover in the phsenomena peculiar to these places 

 the origin of their insalubrity; the information acquired in 

 these particular cases probably leading to the discovery of a 

 common cause of the noxious effects in various localities, 

 and which may have been attributed to very different causes. 



We shall follow the author through the several parts of his 

 xnemoir. — [Edit. Atinales de Chimie et de F/tj/sique.] 



Insalubrity of the Environs of Volteira. 



M. Savi begins by examining the low valleys of the en- 

 virons of Volterra, in which the non-existence of marshes 

 precludes the most common hypothesis, as to the origin of 

 their unhealthiness. This country is formed by very exten- 

 sive marine deposits of the tertiary epoch, and which are 

 chiefly composed of gray argillaceous marls [mattajone) ; these 

 lands, raised in many places by igneous rocks, and altered in 

 others by subterraneous emanations, frequently contain seleni- 

 tic masses impregnated with sulphur, and often with common 

 salt; the igneous rocks constitute the peaks of the mountains ; 

 its sides are formed of this mattajone, raised, altered and im- 

 pregnated with gypsum and common salt; the valleys are also 

 formed o^ mattajone. 



In the bottom of these valleys, not only near water-courses, 

 but also on the sides of the hills, and even at a certain height, 

 malaria exists to such a degree, as not only annually to attack 

 a great part of the inhabitants with obstinate intermittent 

 fevers, but also with fevers of a more dangerous description. 



The author is induced to disregard the hypothesis which 

 attributes the unhealthiness to sudden changes of temperature, 



