THE VOLCANOES AND ROCKS OF PANTELLERIA 659 
on the west to Cala del Cotone on the east, a distance of 2 kilo- 
meters along the coast. 
Rione di Bagno.—Close to the north coast is a small, irregularly 
elliptical plain, the Rione di Bagno (Fig. 2). The western part of 
this is occupied by an oval lake, the Bagno dell’ Acqua, with 
dimensions of about 600 by 500 meters, the surface being only 2 
meters above sea-level. The lake is shallow and is evidently the 
remnant of one which formerly covered the whole of the inclosed 
Fic. 2.—Bagno dell’ Acqua, from west 
area. The Rione di Bagno (including the lake) is bounded on the 
west by the precipitous east face of a scarp, the Costa Zeneti, which 
rises to about 200 meters above the lake surface. This ridge is 
continued to the south and southwest, parallel to the course of the 
Lava Gelfiser, inclosing the narrow Valle Silhoumen, which is 
flanked on the east by the towering mass of tumbled lava blocks 
which constitutes the flow (Fig. 3). To the north the Rione is 
bounded by a similar though lower (38 m.) precipice, known as 
Cuddia Nera, which is indubitably a continuation of the Costa 
