96 Prof. Ferrara'ii Acrount of t/ie E(ti//ic/ua/:es 



founded upon a rocky tongue of land between two large and 

 deep bays. The extremity of this point constitutes at this day 

 the centre of the modern city, flatter, transported thither 

 by the water from the interior, and thrown up by the sea, to- 

 gether with the labour of men, has gradually filled up the 

 lateral spaces, and extended the peninsula with this trans- 

 ported and alluvial earth, and formed the present soil. It is 

 now composed in part of calcareous rock, and in part of mud 

 or alluvial earth ; both are traversed by canals and large 

 conduits for the circulation of water for common use, and by 

 common sewers communicating with the neighbouring shore. 

 The adjacent parts present a surface composed of calcareous 

 tufa, and an earthy aggregate tender and friable ; but deeper 

 down it is more durable, and partly siliceous. The cheapness 

 of the tufa and the ease with which it is wrought have caused 

 its adoption as a building stone, contrary to the custom of our 

 ancestors, as appears from the immense excavations and pits 

 about Syracuse, Girgenti, and some others of the ancient cities 

 of Sicily. Till lately, the common cement was composed of 

 a fat earth, to which ashes were sometimes added ; it was 

 called tqjo. Within a few years, lime and sand have been 

 used. But they do not always employ for lime the stone 

 which is hardest and most proper, nor that which requires 

 an equal degree of heat in calcination ; nor are all the pieces 

 while. It is not slaked methodically, nor mingled with that 

 patience which caused the ancients to say that lime should 

 be tempered by the sweat of the brow. And here, indeed, 

 this labour is the more indispensable, as Palermo is destitute of 

 puzzolana, and of those ferruginous earths which render such 

 valuable service to those volcanic towns of the island which 

 can obtain a cement so adhesive and durable. 



The soft rock of the surface serves in large masses for a 

 foundation upon the cla}'. But the brittleness of the rock, 

 and the instability of the earth, its readiness to change from a 

 level at the least motion, or by the action of moisture, which 

 the air and soil of Palermo make permanent, render the foun- 

 dation very far from firm. I have seen pieces of the founda- 

 tion of large edifices so entirely reduced to eaith as to be 

 removed with a spade. This inconvenience exists even when 

 the rock in its natural situation serves as the base. Where a 

 building is raised upon a soil the parts of which are of different 

 natures, it must suffer much from the unequal resistance of this 

 soil. The right side of the royal palace has tor several years 

 been inclining from a perpendicular, in consequence of its hav- 

 ing been placed on the ancient alluvial formation, while the 

 remainder of the building rests on a rock. Sometimes we see 



buildings 



