A RECONNAISSANCE FROM DAVAO. 509 



A considerable amount of chalcedony, and igneous bowlders, mostly 

 andesite, carrying secondary quartz and zeolites was observed at the 

 junction of the Agusan and the Buoy Elvers. These rocks are brought 

 down by the Buoy Eiver from the mountain range which separates the 

 drainage areas of the Agusan Eiver and the Pacific Ocean. We panned 

 some gravel from near the mouth of the Buoy, but could find no colors. 



We left San Eafael early the following morning, floating downstream 

 with the current and arriving at the municipality of Veruela at 7 o'clock 

 at night. The river was straighter and the banks somewhat higher and 

 more timbered. The Agusan is wide and deep at this part of its course, 

 and affords a splendid avenue for transportation, Ijut the covmtry is so 

 thinly populated that very few baticas were encountered. 



In spite of the fact that this region is one of the most marked centers ^ 

 of frequent and intense seismic disturbances, the beds of soft clay and 

 shale which we found outcropping on the river banks lie practically 

 liorizontal and sliow no effects of dynamic action. An estuary leading 

 into a small pond which drains into the Agusan is situated at a place 

 called Maasin, about 3 kilometers south of Veruela. An oixtcrop of soft, 

 blue shale, containing a large variety of fossil shells in an excellent state 

 of preservation occurs on the west bank of this estuary. These fossils, as 

 well as those collected at Tagusap and other places, have been sent to 

 Dr. Smith at Leiden, Holland, for study and comparison. 



Veruela was the first so-called Christian to'wn that we entered after leaving 

 Davao, and it is the largest on the upper Agusan. I should judge its population 

 to be about 5,000, nearly equalljr divided between Christian Visayans and con- 

 quistas or Mandayan converts. The principal pursuit of the inhabitants is the 

 cultivation of abacft and rice. 



The river at Veruela is considerablj' wider and deeper than at Moncayo, but 

 not as swift. According to our rough measurements it is 61 meters wide, about 

 2.3 meters deep, and has a surface velocity of approximately 2.17 kilometers per 

 hour. These figures correspond to a discharge of about 9.5..5 cubic meters per 

 second as against G4.5 near iloncayo. 



The banks of the river about a kilometer below Veruela gradually 

 l)ecome lower, until they disajjpear entirely; the main channel is choked 

 with vegetation and the current is very much reduced. In place of the 

 splendid river, there is a swampy jungle with alternating, swift, tortuous, 

 and narrow channels and again wider stretches of almost calm water. 

 This portion is termed Lake Linao and is a part of the Agusan Eiver 

 system. The lake is probably formed by a local depression of the sur- 

 face, attendant upon a movement of the earth's crust. There are several 

 lakes in this basin, but their boundaries are not well defined and a channel 

 connects all. 



Clavijo was reached in the afternoon. Tins to\vn consists of one 

 church with corriigated iron roof, and five dilapidated nipa huts, all but 

 two of which were abandoned at the time of our visit. 



7S322 7 



