RECONNAISSANCE OF SOUTHEASTERN LUZON. 455 



view from the vicinity of Bato Lake. Isarog lias the largest base of any 

 of .the peaks and was onee a high volcano. It has suffered erosion to 

 a great extent. May on, on the south, retains its nearly perfect form. 

 The volcanic nature of the central portion of the range is more appa- 

 rent when it is seen from the east, whence the crater of Malinao is visible. 



The Gulf of Albay partially interrupts the continuity of the cordillera 

 to the south of Mayon. The next group of peaks, which are here called 

 the Pocdol Mountains, occupies the country between Albay Gulf and 

 Sorsogon Bay. The elevations of some of the highest points which are 

 situated in the eastern part of the area are 1,099, 1,037, 1,027, and 96G 

 meters, and there are a number of others which approach these altitudes. 

 Certain of the peaks appear to be of volcanic origin, but there are no dis- 

 tinct cone?. This mountainous area descends rather abniptly toward 

 Albay Gulf, but to the westward has a long slope. 



The third division of the Southeastern Cordillera is situated in the 

 peninsula area which constitutes the larger part of Sorsogon Province. It 

 is dominated by Bulusan Volcano, the cone of which has an elevation of 

 1,556 meters. A shai-jD peak to the northeast, which is a part of Bulusan, 

 reaches 1,215 meters. The north and east slopes of the volcano descend 

 quite regularly toward the isthmus and the sea. The country is broken 

 to the south. Mount Jormajan, elevation 726 meters, lies west of Bu- 

 lusan and apart from it. A number of lower mountains, including Mount 

 Bulacan, elevation 860 meters, and Mount Calomutan, elevation 617 

 meters, form a broken ridge lying to the west of the volcano and have the 

 same trend as the cordillera. A low continuation of this ridge is found 

 north of the entrance of Sorsogon Bay. 



Jagor has written : 



"Bulusan is surprisingly like Vesuvius in outline. Like its prototype it has 

 two peaks. The western one, a bell-shaped summit, is the eruption cone. The 

 eastern apex is a tall rugged mound, probably the remains of a huge crater. 

 As in Vesuvius, the present crater is in the center of the extinct cone." 



Jagor saw the volcano only from the sea. A closer inspection shows 

 that it is not so similar to Vesuvius as he has stated. The cone is not 

 in the center of an extinct crater, but has been built on the western rim 

 of an irregularly truncated peak. On the west, the slopes of the cone 

 blend with those of the older part of the mountain. A depression is 

 found between the cone and the sharp peak which Jagor thought to be 

 the remnant of an outer crater. 



Mr. Bloomfield, teacher of agriculture in the provincial school of Sorsogon, 

 ascended the cone. He states that the crater in the summit is about 300 meters 

 in diameter and 50 meters deep. It contains some sulphur deposits. On the 

 western and northwestern inner slopes of the rim there are two vents in which 

 there is slight solfataric action. On the outer, southeastern slope there are 

 three vents or small craters. The highest one is dry. The lower two. which are 

 about 75 meters in diameter, contain water. 



