and Vegetation of- Sicily. 109 



stone is easily worked, but it soon decays, and it may even be 

 said to rot; and it renders the buildings in that calcareous- 

 country by no means durable. The earthy calcareous form- 

 ation, which may also be called argillaceous marl, since it is 

 mixed with siliceous earth and with clay, forms the small hills 

 and extensive plains of Sicily: it is in this that deposits of 

 shells of the ancient sea are discovered, masses of sulphuret of 

 iron, and the mines of salt and of sulphur in which this island 

 is so extremely rich. It is in this formation that the lavas of 

 the ancient volcanoes are found buried around Etna, and in 

 volcanic Sicily, which extends from Etna to Gape Passaro, 

 where, in fact, besides the lavas buried in the earthy calcareous 

 formation, or marl, there appear traces of the ancient fires of 

 this part of the isle mixed with the shell limestone, and the 

 beds alternate with it for a surprising number of times. Where- 

 ever these formations prevail, we find throughout Sicily masses 

 of gypsum ; they are observed in the intervals between the 

 mountains of Pelorus, in the volcanic limestone of the south 

 of Sicily, in the interior behind Alimena, where they consti- 

 tute some miles of heights and of low lands, as well as in the 

 west of the island. In the calcareous formations posterior to 

 the primitive are found quartzose and siliceous pebbles, agates, 

 jaspers, coloured stones, in which the island is extremely rich, 

 and bituminous rocks, from which, most probably, naphtha 

 exudes, and petroleum issues in many places. Pieces of amber 

 and of asphaltum are found among the argillaceous beds. 

 Beautiful crystallisations of sulphur, of sulphate of barytes, 

 and of sulphate of strontian, are discovered in the clefts, and 

 in the cavities in the sulphur mines. The limestone of all the 

 formations, whenever it is sufficiently compact to receive a 

 polish, affords the immense variety of marbles of different 

 colours, for which Sicily is so very famous. 



The perfect resemblance * of the two opposite countries of 

 Sicily and of Italy, and the continued direction of the range of 

 Apennines, prove their ancient union, and compel us to con- 

 sider the straits of Messina as a valley formed by the two 

 ranges of mountains which extend parallel to each other, and 

 into the interior of the two countries. The forces of nature 

 acting in an ordinary manner could not produce this separa- 

 tion ; it therefore, very probably, took place in the last cata- 

 strophe which modified the surface of our globe, and esta- 

 blished the present system. 



* Dr. Daubeny observes on the gneiss of Messina, " This is the form- 

 ation which probably extends on the Italian side of the straits, if I may 

 judge from the specimens I brought from the celebrated rock of Scylla." 



