GEOLOGIC RECONNAISSANCE OF MINDANAO AND SULU. 481 



The region around Camp Keithley^ owing to its altitude is much cooler 

 than the low country and the climate is correspondingly invigorating. 

 However, at certain times of the year, particularly in Deeeraber and 

 January these posts are said to be very disagreeable, as they are cold and 

 raw like the New England coast of the United States in the spring time. 



Typhoons are said not to occur in the latitude of Mindanao and the 

 Sulu Islands. The evident reason for this is that the cyclonic storms, 

 which have their origin in the Pacific are formed in a latitude much 

 north of that of Mindanao and as they pass westward thej^ are constantly 

 curving to the north, partly owing to the original, clockwise movement of 

 cyclones north of the equator and partly because of their apiDroaeh to the 

 continent of Asia. According to Father Algue, Director of the Philip- 

 pine Weather Bureau, a few cyclones form in the Sulu Sea, but these 

 attain no great imjiortance either in frequency or in intensity. 



Plate XXIX of Father Algue's "Cyclones of the Far Bast" ^- shows 

 the mean trajectories of cyclones which pass over or near the Archipelago. 

 It is very interesting in that it reveals how very generally Mindanao and 

 the Sulu group escape these destructive storms. This fact is of the first 

 importance in view of damage which such storms might inflict on crops, 

 particularly on hemp which grows to heights varying from 10 to 18 feet, 

 and because of the relative imnnmity from danger to vessels, such as 

 interisland trading ships, Moro vintas and pearling boats. 



VI. NAHRATIVE OF THE EXPEDITION". 



Zamboanga, the first point visited by me, is situated about 3 miles 

 from the nearest foothills at the edge of a flat plain of considerable area 

 at the foot of the long, narrow peninsula of the same name. (See map, 

 Plate I.) To the east is a long stretch of salt-water marsh and in its 

 rear is a scarcely less elevated tract which is taken up with paddy fields. 

 If tlie Tumaga Eiver liad kept its initial direction, it would cut through 

 the heart of the city, as it is, it curves to the east and enters the sea op- 

 posite Sakol Island. The substructure of this jDlain is coral, the super- 

 structure, silt and coarse detrital material from the hills to the north. 



Zamboanga is essentially a "gate city" and a study of the map will 

 show its central, commanding position with reference to steamship routes. 

 In fact this is the main feature controlling its location. It is not situated 

 on a large river by which communication can be maintained with the 

 interior and for this reason its jDOsition is not favorable as is that of 

 Manila, which is on a plain on the coast and at the same time on the 

 banks of a large stream which taps a great stretch of the interior. Cota- 

 bato, on the Rio Grande de Mindanao, is also fa\oral:)]y located and 

 it will probably expand when the immense possibilities of the country to 

 which it holds the key are understood. 



^ Algnf, Jose: The Cyclones of the Far East, Bureau of Public Printing, Manila, 

 1904. 



