432 The Philippine Journal of Science 1923 



A tramp along Mount Santo Tomas Trail confirms this view, 

 and from the upper elevations the hanging valley of Loacan is 

 also recognized as an old wide stream valley robbed of its head- 

 waters by some piratical tributary or tributaries of Gold Creek 

 and left hanging on the wall of Bued River Canon through a 

 process of rapid erosion of the master stream (Plate 9, fig. 1, 

 and Plate 10, fig. 2). 



An automobile ride from Baguio to Trinidad with its aston- 

 ishing variety of scenery, the gently rolling valley and hills, 

 the sudden entrance into the narrow shelf-cut road of Trinidad 

 River Canon and the equally sudden appearance of Trinidad 

 plain impress all with their pleasing contrasts. A walk from 

 the capitol at Trinidad for a short distance along the Mountain 

 Trail demonstrates the great differences between the Baguio 

 Plateau and Trinidad Valley and the sharply chiseled ridges and 

 acute V-shaped valleys of the country traversed by the Moun- 

 tain Trail. Such are the temptations placed before the student 

 of historical geology and physiography which cause him to 

 dream and embolden him to attempt a reconstruction of the 

 Past. 



LOACAN VALLEY 



From the Mount Santo Tomas Trail looking eastward, one sees 

 the splendid hanging valley of Loacan with its wide, gently 

 sweeping slopes, and pictures of a quiet-flowing stream in the 

 middle of a wide shallow valley of the New England country 

 come to mind. The last impression at once fades when, upon 

 rounding another turn of the trail, the steep canons of upper 

 Bued River come into view, and one sees the wall over which 

 the now feeble waters of Loacan Creek descend abruptly to join 

 the waters of the present-day Bued River. A short automobile 

 drive through Camp John Hay across the easily eroded tuffs of 

 the Baguio formation brings us to this valley. The slopes are 

 those of early old age, but the stream now occupying the valley 

 center is very small. A view at the upper part of the present 

 valley clearly indicates that the piratical Gold Creek has success- 

 fully beheaded this ancient stream. The trend of the present 

 Loacan Valley indicates a consequent southwestward-flowing 

 stream, and the recent movements along the stream course 

 athwart Mount Santo Tomas fault may have been the cause of 

 the rapid capture of its lower portion. This explanation is 

 even more apparent when one considers the highly youthful 

 character of upper Bued River during the descent of the Zigzag. 



