LINOSA AND ITS ROCKS 9 



west side is a vertical dike about 70 centimeters wide, of finely vesicular 

 black basalt, which cuts through the yellow tuff beds, but not through 

 the black scoriae above. The sides of this dike show distinct marks 

 of flow, and it has not altered appreciably the yellow tuffs. 



Of the cinder and lava cones, which mark the second period of 

 vulcanicity, the highest is Monte Vulcano, immediately southeast of 

 Monte Calcarella, and on the south coast of the island. The summit 

 of this I measured with an aneroid as 199 meters above sea-level, 

 while the Italian military map gives it as 195 meters, and the ItaHan 

 hydrographic map as 160.^ About 14 meters below the summit of 

 this volcano is a well-preserved, circular crater, about 100 meters in 

 diameter and 30 meters deep, the steep walls composed of scoria and 

 blocks of lava. On the south slope of the volcano, toward Monte 

 Levante, are many vesicular lava flows, interbedded with tuffs, and 

 lava flows and cinder slopes are also seen on the east side. On the 

 west side, some 80 meters below the summit, is an almost horizontal 

 plateau, the upper surface of a series of six or eight lava flows, each a 

 meter or so thick, frequently with a rough columnar structure, and 

 separated from each other by thin layers of scoriaceous material. 

 On the upper edge of this plateau is a natural pit, with an orifice 

 about two by three meters across, and about fifteen meters deep, so 

 far as one can see, from which issues constantly a strong stream 

 of cold air, resembling a somewhat similar orifice at the Kaimeni, on 

 Methana, in Greece, and the bufadores of Catalonia. On the south 

 slope, below this plateau, are some bedded tuffs and a steep sciarra of 

 lapilh which extends down to the water's edge and which closely 

 resembles that of Stromboli. Elsewhere the sides of the cone are 

 covered with scoriae and blocks of lava, with small lava flows here 

 and there. As was noted above, the products of this volcano cover 

 the lower slopes of Monte Calcarella on the northwest and of Monte 

 Levante on the southeast, thus showing its later date. 



The next highest cone of Linosa is Monte Rosso, in the northeast 

 corner of the island. According to my aneroid this is 196 meters 

 high, while the ItaHan maps give it as 186 meters, and the English 

 one as 610 feet (186"^), so that it is only a trifle lower than Monte 



I The British Admiralty chart gives the height as 525 feet (129™), which is 

 certainly much too low, and is possibly an error for 625 feet (19 1™). 



