LINOSA AND ITS ROCKS 7 



western rim being about 1 50 meters above the sandy and lava-covered 

 plain to the west and about 20 meters above the crater floor. To the 

 east its tuffs are lost beneath the lavas and cinders of Monte Rosso. 

 This northerly crater is older than its companion, as the tuffs of the 

 latter cover part of its southern side, and it may be considered the 

 oldest on the island, in view of its poor preservation and central 

 position. 



The southern crater, which is called II Fosso, presents a flat, 

 elliptical floor, of about the same size as that of the preceding, which 

 is planted in vines and cactus. This crater is bounded on the north, 

 west, and south by a well-defined rim of yellow and greenish-gray 

 tuffs, which also contain blocks of compact basalt. This ridge 

 reaches a height on the west, Monte Bandiera, of 102 meters, and on 

 the south of 148 meters, this southern rim being known as Monte 

 Calcarella. The south slopes of Calcarella are partly covered by the 

 scoriae of Monte Vulcano, and to the east the low, ill-defined rim of 

 II Fosso is almost wholly buried beneath the lavas and ashes of this 

 same volcano. A gap in the ridge on the southwest, between Monti 

 Bandiera and Calcarella, gives access to the crater floor. 



At the southeast corner of the island is a third tuff cone, that of 

 Monte Levante.^ Of this only the northern half remains, the southern 

 portion having been washed away by the waves, forming a pre- 

 cipitous chff and exposing a fine section, in an inaccessible outlying 

 pinnacle of which was seen a dike of black basalt. What remains 

 of the cone consists of thin-bedded yellow and dark, greenish-gray 

 tuffs, which contain numerous, rather large, angular blocks of com- 

 pact basalt. On the flat summit of the ridge, which is 92 meters 

 above sea-level, weathering has developed in the tuff about these 

 blocks a series of concentric thin shells, which resemble a nest of 

 hemispherical basins in which the blocks lie. None of these shells 

 were seen covering the blocks, that is, with the convexity uppermost. 

 The origin of this pecuHar structure is uncertain and, while it seems 

 to be made evident by weathering, yet its cause must apparently be 

 attributed to some other agency, possibly to the vibrations set up in 



I This is the name as given on the ItaHan mihtary map, and the one by which 

 it may best be called here, though my guide called it Monte Calcarella. But this 

 last name is given on all the maps to the southern rim of the crater just described. 



