INACCESSIBLE VALLEYS 



characteristic type of the forest vegetation of the Sierra 

 Nevada range. 



Professor J. D. Whitney, formerly State Geologist of 

 California, thus characterises the valley in his Yosemite 

 Gtcide Book : 



The principal features of the Yosemite, and those by which it is 

 distinguished from all other known valleys, are : first, the near 

 approach to verticality of its walls ; second, their great height, not 

 only absolutely, but as compared with the width of the valley 

 itself ; and, finally, the very small amount of talus or dihris at the 

 base of these gigantic clifis. These are the great characteristic 

 features of the Yosemite throughout its whole length ; but, besides 

 these, there are many other striking peculiarities and features, both 

 of sublimity and beauty, which can hardly be surpassed, if equalled, 

 by those of any mountain valleys in the world. Either the domes, 

 or the waterfalls of the Yosemite, or any single one of them even, 

 would be sufficient in any European country to attract travellers 

 from far and wide. 



The origin of this wonderful valley has been a puzzle 

 even to geologists. After describing the formation of 

 most of the valleys of the Sierra Nevada as being due to 

 denudation, Professor Whitney says : 



The eroded canons of the Sierra, however, whose formation is due 

 to the action of water, never have vertical walls, nor do their sides 

 present the peculiar angular forms which are seen in the Yosemite, 

 a^, for instance, in El Capitan, where two perpendicular surfaces 

 of smooth granite, more than 3,000 feet high, meet each other at a 

 right angle. These squarely-cut, re-entering angles, like those 

 below El Capitan, and between Cathedral Rock and the Sentinel, or 

 in the lUilouette canon, were never produced by ordinary erosion. 

 Much less could any such cause be called in to account for the 

 peculiar formation of the Half Dome, the vertical portion of which 

 is all above the ordinary level of the walls of the valley, rising 2,000 ' 

 feet, in sublime isolation, above any point which could have been 

 reached by denuding agencies, even supposing the current of water 

 to have filled the whole valley. 



He then goes on to discuss the possible agency of ice, 

 which he dismisses as quite inadequate. Valleys formed 

 by fissures of the earth's crust are then discussed, and it is 

 shown that the Yosemite cannot have been formed in this 

 way, partly because it is too wide, and also because there 

 is no correspondence between the opposite sides. 



In default of any of the usually accepted theories of 



