630 



ISLAND OF PALMA. 



Fig. 697. 



[Oh. XXIX. 



View of the Isle of Palma, and of the entrance into the central cavity or Caldera. 

 From Von Buch's " Canary Islands." 



The annexed section (fig. 698) passes through the island from 

 Santa Cruz de Palina to Briera Point, or from southeast to northwest 

 (see map, p. 628). It has been drawn up on a true scale of heights 

 and horizontal distances from the observations of Mr. Hartung and 

 my own. 



Fiar. 698. 



Section of the Island of Palma, from Point Briera, on the northwest, to Santa Cruz de Palma, 

 on the southeast. See map, fig. 695, p. 628. 



«, 5. The Caldera (height of a, 6000 feet). 



c. Commencement of steeper dip. 



d. Santa Cruz de Palma or Tedote. 



e. Lateral cone, 3940 feet above the sea (Vidal's Map). 

 /. Briera Point. 



cj. One of several outliers of the upper formation in centre of Caldera. 

 S. P. Half-buried cone and crater of San Pedro. 



The lavas are seen to be slightly inclined near the sea at Santa 

 Cruz, where we observed them flowing round the cone of San Pedro, 

 which they have more than half buried without entering the crater. 

 On starting from the same part of the seacoast, and ascending the 

 deep Barranco de la Madera, we saw just below c the basaltic lavas 

 dipping at an angle of 5 degrees, there being no dikes in that region. 

 Farther up, where the dikes w T ere still scarce, the dip of the beds 

 increases to 10 and 15 degrees, and they become still steeper as they 

 approach the Caldera at b, where dikes abound. 



The section (fig. 699) is at right angles to the preceding, and cuts 

 through the cone in the direction of the great Barranco, or from north- 

 east to southwest. 



The lowest of the two slanting lines, m, i, descending from the 

 Caldera to the sea along the bottom of the Barranco, represents the 

 present bed of the torrent ; the upper line, k, I, the height at which 

 beds of gravel, elevated high above the present river-channel, are visi- 

 ble in detached patches, shown by dotted spaces at k, and to the south- 

 west of it, on the same slope. These, and the continuous stratified 



