SOOLOO ISLANDS. 545 
cones, and several of these were perfectly regular and even in their 
steep slopes. ‘The sides of two inclined at an angle of forty degrees. 
Some of the cones run up almost to a pointed summit, while others 
were broken off and had the common oblique truncation of volcanic 
peaks; others were still more broken, and gullied by denudation. 
We passed by two small islands, called from their forms Asses’ Ears, 
which appeared to be the remains of cones. 
The island of Jolo has the same volcanic constitution. The outline 
of the principal range rises into several conical peaks, and the declivi- 
ties slope gradually away at a small angle like the larger volcanic 
mountains. ‘They belong to the several craters which united together 
form the main range. ‘The most elevated points are about two thou- 
sand feet above the sea. Some of the cones stand a little isolated, and 
their smooth declivities remind us of the Hawaiian Islands. The 
angle of inclination is ten to twelve degrees or less. 
The jealousy of the authorities prevented our taking an excursion 
into the interior of Jolo. The loose blocks that lay about the village 
of Soung were cellular lavas, and an ash-coloured tufa resembling 
that of Manilla. A small uninhabited island off the harbour, where a 
few hours were spent, consisted of a coarse volcanic breccia, contain- 
ing large angular masses of lava, compact and cellular. ‘There were 
two hills in the small island, about three hundred feet high, which 
were probably parts of a former cone; between them lay a salt water 
lagoon communicating with the sea on the north. Other islands in 
the vicinity had similar features, and probably a similar origin; but 
we had no opportunity to examine them. 
No evidences of change of level were observed in the group. The 
coral reefs seen were all submerged, and in no case formed plat- 
forms at the water level: as far as this goes, it tends to prove a subsi- 
dence rather than an elevation. It seemed surprising that so extensive 
coral shoals should not have reached the surface. This is partially 
attributable to the volcanic character of the group, whose fires must 
have been in operation to a very late period, and were to a great 
extent submarine in their action. Yet it is possible that extensive 
subsidences may have taken place; and if there are any changes in 
progress they are probably of this character. 
Notwithstanding the abundance of rocks that meet one on every 
side, the island of Jolo, like others of volcanic character in a climate 
sufficiently moist, is abundantly fertile, and has an air of luxuriance 
which belongs peculiarly to the tropics. 
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