RECONNAISSANCE OF MINDANAO AND SULU : III. 365 



caved in and I found the entrance with difficulty. I think this locality 

 an exceptionally favorable one for further exploration, because the coal 

 outcrops about fourteen meters from the Siay River and has only a 

 moderate inclination. Lighters could be towed up this river by small 

 steam launches within a few yards of the mine mouth. Of course, at the 

 present time the river is full of snags but these could easily be cleared 

 out. 



Analysis of Sibuguey coal. 



Per cent. 



Moisture 6.55 



Volatile combustible matter 41.95 



Fixed carbon 48.10 



Ash 3.40 



Sulphur 0.26 



Sibuguey Bay is well protected and is not in the typhoon region so 

 that safe anchorage for ships could be obtained. However, there is one 

 difficulty : Extensive reefs are found all around this coast, making navi- 

 gation exceedingly difficult, but this condition is largely ameliorated by 

 the fact that the Coast and Geodetic Survey has completed accurate charts 

 of all the waters near the Siay Eiver. I believe that the coal measures, 

 which are not at all metamorphosed on the eastern side of Sibuguey Bay, 

 continue around and into the Zamboanga Peninsula, where they may be 

 metamorphosed with the schists. If the coal should continue, there is 

 great likelihood of a better grade being found in the lower part of the 

 peninsula, where great pressure has been exerted on the rocks. This can 

 only be ascertained by drilling or sinking a shaft, as I know of no place 

 where the streams have cut deep enough on the sides of the anticline to 

 expose the underlying coal measures. 



At the foot of the Tres Eeyes Peaks, not far from Margus Tubig, on 

 Dumanquilas Bay, Mr. Cleveland has discovered and partially opened up 

 a half-meter seam of coal, which in physical and chemical characteristics 

 is semi-anthracite. Whether or not there is a thicker seam below has 

 not been determined. Below is an analysis of this coal from a sample 

 collected by me. About 100 meters from the first outcrop is a second 

 where the coal is entirely metamorphosed, resembling veiy closely the 

 columnar structure of basalt, the well known basalt "columns." This is 

 well shown in the photograph on Plate V. 



Analysis of Tres Reyes coal.* 



Per ceut. 



Moisture 1.85 



Volatile combustible matter 10.43 



Fi.Ked carbon 82.34 



Ash " . 5.38 

 Calorific value, 7,695 calories. 



* Analysis by Forest B. Beyer, Bureau of Science. 



