X, A, 5 Pratt: Persistence of Philippine Coal Beds 299 



and that evidence of nonuniform conditions has been obtained 

 in some cases, but that nowhere have large beds been shov^n 

 to pinch out entirely by reason of the limited area of the original 

 deposition. It is to be noted that the coals of higher quality 

 are mostly faulted and that the lower grade coals are most reg- 

 ular. This is a condition which would be anticipated, since 

 all the coals are of approximately the same age and only by 

 more or less violent dynamism have the removal of water and 

 the increase in the proportion of fixed carbon necessary to 

 improve the quality been accomplished. 



Judging from past experience, then, the development of Phil- 

 ippine coal fields must contend with minor faulting and the 

 possibility of varying thicknesses of coal due to irregular original 

 deposition. 



