FORMEi; GLACIATION OF THE SOUTHERN HIGH SIEHEA. 39 



snow and ice. The direction, during all the upper piirt of its course, is 

 parallel with the trend of the Sierra, and an inspection of the map will show 

 at once how limited its area of drainage in the higher part of the range is, 

 as compared with the other principal rivers farther north. 



Three rivers of the Sierra Nevada presented in their upper basins all the 

 conditions necessary for the formation of large mers dc glace, and they were 

 thus occupied at no very distant period : these were the King's, the San 

 Joaquin, and the Tuolumne. Of these grand glacial masses probably that 

 of King's River was the largest, because the area of drainage of this river 

 is greater than that of either of the other rivers named, while the average 

 height of the chain in this portion of its extension is greatest. The most 

 elevated region drained bv the Kin<>;'s is that included between Mount 

 Brewer, Mount Tyndall, and Kearsarge Mountain, there being here a trian- 

 gular area, the lowest part of which has an altitude of over 10,000 feet above 

 the sea-level. Tlie North Fork of the Kinsr's does not head in the nuiin 

 range of the Sierra, but to the west of the Mount Goddard Group, being 

 lapped around by the South Fork of the San Joaquin. The length, in a 

 direction parallel to the axis of the Sierra, of the area diaincd by branches 

 of King's River, is about fifty miles ; but they only head up as high as the 

 main divide for a distance of about thirty miles. The North Foi-k joins the 

 main stream about six miles below the junction of the Middle and South 

 Forks, and this is about thirt}' miles in a straight line from the crest of the 

 Sierra. The valley in the neighbofhood of the junction of the three branches 

 is from 6,000 to 7,000 feet in altitude, and was formerly occupied )>y the 

 united ice-streams comins; in from above. Allowino; that one third of the 

 surface of the basin above this point was covered by the King's River system 

 of glaciers, the connected ice-mass must have had an area of somewhat over 

 300 square miles. All through this region, the lower portions of the valleys 

 are smoothed, scratched, and polished, and lateral and medial moraines occur 

 on the grandest scale ; but nowhere were any markings observed at a lower 

 altitude than 4,000 feet above the sea-level. Professor Brewer, in his notes 

 of his examination of this re<^'-ion in 1864, says : " The entire absence of 

 observed glacial traces at lower levels makes it almost certain to me that the 

 glaciers did not descend to below 3,000 feet, and indeed no traces have been 

 seen below 4,000 feet." 



The moraines in the upper portion of the King's River basin are among 

 the largest and most perfect Avhich liave been observed anywhere in the 



