PIlfON EANGE. 551 



usually free from saline ingredients. The temperature of several of the 

 pools was taken, showing a variation from 51° to 109°. At the base of' 

 the Pinon Range, on the line of the old Overland Stage Road, are found 

 springs of clear but tepid waters highly charged with sulphur. 



Pinon Range,^ — The range of mountains which lies next west of the 

 Diamond Range, and to the north is separated from the East Humboldt 

 Range by the broad plain of Huntington Valley, derives its name from the 

 very considerable growth of coniferous forests that are scattered over its 

 sunmiits and slopes. It extends from Dixie Pass, just north of the line of 

 40° 30', where it terminates abruptly, southward to Swallow Canon, near 

 the line of 39° 30'. The 116th meridian west, from Greenwich follows for a 

 long distance the crest of its ridge. It is in general a well-defined single 

 ridge, and for the greater part of its length barely averages six miles in 

 width, having a varied broken outline, with isolated peaks rising between 

 3,000 and 4,000 feet above the valley, and then rapidly falling off into low 

 depressions and easy passes. 



Geologically, the Pinon Range presents several features which are of 

 special interest, if not exceptional, in the structure of Great Basin ranges. 

 Among these, the absence of granite throughout its entire length is worthy 

 of remark, as but few ranges are seen in which granite or related rocks do not 

 occupy more or less area, and to the influence of which the present structural 

 features of the neighboring Palaeozoic formations may not in part be traced. 

 But on the other hand there are seen here the entire conformable series rep- 

 resented from the Cambrian schists and quartzites, through the great thick- 

 ness of Silurian limestone, Ogden Quartzite, and nearly, if not quite, to the 

 top of the Wahsatch limestone, lying highly inclined, and exposing about 

 14,000 feet of strata. In structure, we find, dipping both east and west, 

 simple monoclinal ridges, gentle synclinal folds, and broad anticlinal axes. 

 Everything later than the Wahsatch limestone appears to be wanting until 

 Tertiary times, but of the latter deposits there have been recognized skirt- 

 ing the older upheaval the non-conformable upturned Green River Eocene, 

 with the later nearly horizontal Humboldt Pliocene beds. The volcanic 



'In part from notes furnished by Mr. CLirence King. 



