GEOLOGIC RECONNAISSANCE OP MINDANAO AND SULU. 487 



boat and touch the branches of the trees, and we finally anchored in the 

 narrow straits between Siasi and Lapac Islands. We had but one or two 

 hours of daylight at this point, but a short excursion inland gave us a 

 fairly good idea of the geology and soil of Siasi. The soil, as in Sulu, 

 is a rich, red volcanic material, and the underlying rock, wherever I saw 

 it, was andesite or basalt, which is frequently difficult to classify exactly, 

 because of the weathering to which it has been subjected. Very little 

 timber is seen on this island, at least not on the side at which we touched, 

 and there are no large streams. However, a dense growth of cogon grass 

 prevents serious damage from erosion. If this grass were not present, 

 loss would surely result owing to the lack of forest. On the other hand 

 cogon, as in other parts of the islands, is a serious menace to agriculture. 

 It is usually the custom of the natives annually to burn off this grass, 

 but this method only affords temporary relief. A better way and one 

 which is being practiced with success in many localities is to plow the 

 cogon under for two or three seasons, when the roots rot and not only 

 is the grass killed, but the soil is further enriched. • 



The next point visited was the large and geologically little known 

 Island of Basilan. A portion of this island was occupied by the Spanish 

 government, which had a small naval station at Isabela on the north 

 coast. This has been abandoned since American occupation and the 

 place has consequently fallen into neglect and decay. 



But little geographical exploration has been clone in Basilan. Mr. Dean C. 

 Worcester and his party visited it about the year 1892, and the following is taken 

 from his account." 



"Isabela, the capital of Basilau, is a small place of less than 1,000 souls. The 

 only Spaniards there are the officials and the Jesuit priest. The to^vn is on high 

 ground, which slopes sharply down to the edge of the channel separating Basilan 

 from the little island called Malamaui. This channel, although extremely narrow, 

 is very deep, and large vessels can come close inshore. Tremendous currents rush 

 through it with the ebb and flow of the tides. 



"Isabela is a supply station for gunboats, the coal yard and magazines being 

 located in Malamaiii, just across from the town. To defend the important stores 

 which they contain there is only a ridiculous old limestone fort on a neighboring 

 hill, armed with two or three antiquated smoothbore cannon, and garrisoned by 

 a few marines. 



"The Moros of Basilan, locally called Yacans, have always borne a bad reputation, 

 but at the time of our visit they were held in check by a remarkable man known 

 as Data (Chief) Pedro." 



A j)ieture of the fort mentioned above is shown on Plate XV. 



Only two short trips were made into the country back of Isabela; the 

 same basaltic flows and rich red soils exist here as in Sulu and Siasi. 

 Vulcanism does not appear to be as recent in Basilan as in Sulu. At no 

 place did I find that the streams had cut through the lava capping and , 

 exposed the sediments which I feel sure lie beneath. 



M Worcester, Dean C. : The Philippine Islands and their People. Maomillan, 

 (1901), 144. 



