ERUPTION OF TAAL VOLCANO. 73 



mately that over which the average thickness of the fall of mud exceeded 

 1 centimeter. The limits of these two areas have been fixed from 

 personal notes. Over the largest area, 1,940 square kilometers, the mud 

 formed a noticeable continuous coating, more than 1 millimeter (approx- 

 imately) in thickness; beyond this limit it was only visible by close 

 observation. Information from people in the near-by to^Mis has been 

 relied upon for the extreme eastern and western limits of this area.^^ 



The greatest fall of material within the devastated area was on the 

 west slope of the volcano. The maximum thickness of 2 meters noted 

 here occurred where the ash and small fragments had drifted into an 

 old water course. However, the ridges adjacent were all but bare, and 

 therefore an estimate of 20 to 30 centimeters for the average maximum 

 depth of fall for this vicinity is probably reasonable. 



The map showing the distribution of ejecta affords an interesting 

 study in the position of the crater relative to the centers of the three 

 areas outlined and in the varying direction of the longer axes of these 

 areas. Evidently the distribution was governed by forces from two 

 directions. The area of devastation, due solely to volcanic action, lies 

 considerably to the west of the crater, its center is approximately 4 

 kilometers N. 65° W. of the latter. The center of the largest area, the 

 limits of which were determined mainly by the wind, lies northeast of 

 the crater. To the southwest the limits of the three areas are very 

 close together, showing that in this direction the material traveled only 

 as far as the expanding cloud carried it. It is concluded that the 

 prevailing wind encountered by the eruption cloud, especially in its upper 



" At Santa Cruz, La Laguna, according to Dr. R. A. Brown, a slight fall of 

 mud began just fifteen minutes after he was awakened by the noise of the eruption. 

 The mud was barely noticeable the next morning. 



At Marigondon, Cavite, the mud "was as the dust which gathers on the show 

 eases of the open shops after the street sweepers have passed along an unsprinkled 

 street." (Personal letter from municipal president.) 



The mud could be distinguished from Cabuyao to Lipa on the Batanga3 

 extension of the Manila and Dagupan Railroad. 



No mud fell in Cuenca, Taal, Tuy or Nasugbu, Batangas Province. 



Dust fell in Manila six to eight hours after the eruption, and was visible on 

 furniture and other smooth surfaces the next morning. 



Comparing these areas to similar areas from the eruption of Mont Pele6 in 

 May, 1902 (see Hovey, E. 0., Am. Journ. 8d. (1902), 14, 320), it develops that 

 Taal devastated more than twice the area that Mont Pele6 did although the 

 eruption was probably of much lesser magnitude. The ashes from Peleg spread 

 over an area probably ten times as great as those from Taal. The crater of 

 Mont Peleg is 1,280 meters above sea level, while Taal in places is as low as 100 

 meters. Thus the eruption from Mont Pele4 had much more room for downward 

 expansion, and the same energy at the crater threw its ejecta much higher in 

 the air than in the case of Taal. 



