212 Adventures in Scenery 



Beyond El Portal the ice of the Yosemite Glacier (of the earlier 

 or El Portal stage) did not go. Beyond El Portal the gorge 

 loses its U-shape and in cross section becomes V-shaped. Be- 

 low El Portal, through the belt of metamorphosed sedimentary 

 rocks (remnant of the ancient roof which lay over the great 

 batholith) the river has cut a deep gorge the walls of which 

 rise abruptly and steeply on either side. 



A dozen kinds or types of rocks occur in a belt a few miles 

 in width where crossed by the Merced River. Here in brief is 

 the key to the Yosemite Valley, one of the most unique and 

 stupendously overwhelming in grandeur, in the world. The 

 valley is 3,000 to 4,000 feet deep, and the enclosing walls rise 

 from a flat nearly level floor in what appear to the observer to 

 be perpendicular precipices. About 5 l /z miles down the valley 

 from the headwall the valley is narrowed, dividing the great 

 chasm into two parts known as the upper and lower chambers. 

 On the north side of the valley, and forming one of the shoul- 

 ders of the narrows, stands El Capitan, a vast monolith of hard 

 massive granite, its wall facing the valley being almost vertical, 

 and rising above the valley floor 3,000 feet. On the south side 

 of the valley and opposite to El Capitan the Cathedral Rocks 

 project into the valley boldly more than a mile, forming the 

 south shoulder of the portal. The rocks are very hard and 

 massive (that is, un jointed) and, like El Capitan, stood fast 

 against the ice of the glaciers. These two promontories form 

 the portal between the upper and lower chambers. 



Above the Cathedral Rocks (east) is a wide embay ment or 

 broadening of the valley. Here the rocks are no longer mas- 

 sive granite (unjointed) but a complex mass of intruded igne- 

 ous rocks (technically diorite and gabbro) which are largely 

 and intensely jointed, and therefore affected by erosion and 

 readily quarriable by glacier ice. The valley wall is deeply dis- 

 sected by ramifying gulches. Craggy slivered spires of more 

 resistant intruded granite stand out in intricately and irregu- 

 larly sculptured forms. The twin shafts of the Cathedral 



